The Testimonium Flavianum is appearing in all the most ancient copies of 'Antiquities of the Jews' (earliest ca. 1050), which was written by the Jewish historian Josephus (37-105?) and published in 93:
Now there was about this time Jesus, a wise man, if it be lawful to call him a man; for he was a doer of wonderful works, a teacher of such men as receive the truth with pleasure. He drew over to him both many of the Jews and many of the Gentiles. He was [the] Christ. And when Pilate, at the suggestion of the principal men amongst us, had condemned him to the cross, those that loved him at the first did not forsake him; for he appeared to them alive again the third day; as the divine prophets had foretold these and ten thousand other wonderful things concerning him. And the tribe of Christians, so named from him, are not extinct at this day.
The first mention of the Testimonium Flavianum, some 225 years after the writing of 'Antiquities', was by the prominent bishop Eusebius, an ardent apologist.

1. General comments:

a) "The problem here is that Josephus' account is too good to be true, too confessional to be impartial, too Christian to be Jewish."
John Dominic Crossan, 'The Historical Jesus, The Life of a Mediterranean Peasant' (1991) (p.373)
Note: this comment applies to the whole Testimonium Flavianum (TF).

Many scholars (including Crossan) claimed that by removing two passages and changing (or deleting) a third one (the one about "He was Christ"), supposedly the work of a latter zealous Christian, the remaining TF would be acceptable as authentic. The three passages are indicated in purple.

b) There were attempts to rewrite the TF with a less pungent Christian flavor, to make it sound more credible as Josephus' creation. Here, I quote an Arabic version first reported by a 10th century Melkite bishop, Agapius, in his book 'Book of the Title'. Today, this version is considered spurious by most scholars, but some of them think that part of it was translated from Josephus' original Testimonium:
"Similarly Josephus [Yusifus], the Hebrew. For he says in the treatises that he has written in the governance of the Jews:
[??? Our author did not seem to have quoted directly from 'Antiquities of the Jews' but rather (loosely) from "memory" (and with personal input!), including the name of Josephus' work! That would explain the differences]
` "At that time there was a wise man called Jesus. His conduct was good, and [he] was known to be virtuous [or: his learning/knowledge was outstanding] [two different translations?]. And many people from among the Jews and the other nations become his disciples.
[Gentile disciples of Jesus! Not even in the gospels!!! But the inspiration might have come from Jerome's Latin version (400) of the TF (see later on this page), which has Gentile followers of Jesus. Also let's notice, there is no "he was Christ"]
` Pilate condemned him to be crucified and to die.
[the rather odd addition of "to die" might be due to the fact that Moslems, according to the Koran, did not believe Jesus died on the cross: "... the Messiah, Isa [Jesus] son of Marium [Mary], the apostle of Allah; and they did not kill him nor did they crucify him, but it appeared to them so ... and they killed him not for sure." (4.157)]
` But whose who had become his disciples did not abandon his discipleship. They reported that he had appeared to them three days after his crucifixion, and that he was alive; accordingly he was perhaps the Messiah,
[notice "perhaps" and (only) "reported", more likely to be thought as being written by a Jew!]
` concerning whom the prophets have recounted wonders.""
Shlomo Pines 10-11, 16, from J.D. Crossan, 'The Historical Jesus'

Notes:
a) This version is so different of the one in 'Antiquities' that the "too good to be true" TF would be the result not only of additional embellished bits but also of significant rewriting.
b) Wm. Whiston (1667-1752), the translator of 'The Complete Works of Josephus' quoted (in Appendix, Dissertation I) no less than five significantly dissimilar renditions of the Testimonium, written by Christian authors in about 360, 400, 1060, 1170 & 1480 (more details in last Section). Therefore the Arabic version is not peculiar and fits very well into those modified TFs. The reason for the differences could be personal bias or/and faulty memory (remembering from a previous reading long ago).
During the same period, Whiston found only three which are as in 'Antiquities' (410, sometime in the 9th century & 1120).

2. Origen and Eusebius testimonies:

a) Origen:
Origen wrote, in about 230:
"... on account of what they had dared to do to James,
[likely reference to Josephus' Ant., XX, IX, 1]
` the brother of Jesus, who was called Christ;
[as in Josephus' Ant., XX, IX, 1: "the brother of Jesus, who was called Christ"
Note: "... him called Christ" would be a less misleading translation]
` and wonderful it is, that while he [Josephus] did not receive Jesus for Christ he did nevertheless bear witness that James was so righteous a man ..." (Comment. in Matth., p. 234)
In Id. Contr. Celsius lib. i. p.35, 36, composed some twenty years later, the same Origen wrote:
"The same Josephus, also, although, he did not believe in Jesus as Christ, ..."
and also:
"... for Josephus testifies in the eighteenth book of his Jewish Antiquities, that John was the Baptist, and that he promised purification to those that were baptized."
proving that Origen knew about John's passage.

Note:
In the later aforementioned book, Origen also related a spurious addition about James (because some scholars consider this passage --which does not show in the old manuscripts-- to be authentic, I will argue for its spuriousness later on this page), as quoted later by Eusebius ('The History of the Church', II, 23).
According to 'Commentary on Matthew' (X, 17), written earlier, here is Origen's comment about the passage in question, with clues about its textual context (see next paragraph for the most likely location of the interpolation).
"he [Josephus] had a mind to set down what was the cause why the people suffered such miseries, till the very holy house is demolished, he said, that these things befell them by the anger of God, on account to of what they had dared to do to James, the brother of Jesus ..."

Here is Ant., XX, XI, 1 (last sentence), followed by the spurious passage in purple (everything fits!):
"But then what actions we were forced to do, or what miseries we [Jews] were enabled to suffer, may be accurately known by such as will peruse those books which I have written about the Jewish war.
[describing "actions" and "miseries" up to the temple destruction]"
"These miseries befell the Jews by way of revenge of James the Righteous, who was the brother of Jesus who was called Christ; [because they had slain him], who was a most righteous person."

b) Eusebius:
According to Eusebius in 'The History of the Church' (HC), I, 11, published 311-325:
"After giving this account of John,
[which Eusebius had just quoted, word by word, as "found in Antiquities Book XVIII"]
` in the same part of his work
[and NOT two chapters earlier, as the TF is located now!]
` he [Josephus] goes on to speak as follows of our Saviour: ... [the TF follows]"
the Jesus' passage was indicated to immediately follow Josephus' testimony about John the Baptist (Ant., XVIII, V, 2) which I quote below, so my readers can compare it with the content and style of the Testimonium:
"Now some of the Jews thought that the destruction of Herod's army came from God, and that very justly, as a punishment of what he did against John, that was called the Baptist: for Herod slew him, who was a good man, and commanded the Jews to exercise virtue, both as to righteousness towards one another, and piety towards God, and so to come to baptism; for that the washing would be acceptable to him, if they made use of it, not in order to the putting away of some sins, but for the purification of the body; supposing still that the soul was thoroughly purified beforehand by righteousness. Now when others came in crowds about him, for they were very greatly moved by hearing his words, Herod, who feared lest the great influence John had over the people might put it into his power and inclination to raise a rebellion, (for they seemed ready to do any thing he should advise,) thought it best, by putting him to death, to prevent any mischief he might cause, and not bring himself into difficulties, by sparing a man who might make him repent of it when it would be too late. Accordingly he was sent a prisoner, out of Herod's suspicious temper, to Macherus, the castle I before mentioned, and was there put to death. Now the Jews had an opinion that the destruction of this army was sent as a punishment upon Herod, and a mark of God's displeasure to him."

The Testimonium (and not the gospels) is used as the main description of Jesus' public life in Eusebius' 'The History of the Church' (HC). Here, its location is "center stage" and its significance capital, considering:
HC, I, 8-9: the birth of Christ
HC, I, 10: the "historical" context at the beginning of the Saviour's preaching with an explanation about the length of his ministry (which starts here some two or three years before Pilate; but a few lines earlier, the same ministry begins under "Pontius Pilate in the fourth year of his governorship"!!!) and a short section about his disciples/apostles.
HC, I, 11, titled "The Evidence about John the Baptist and the Christ"
- John the Baptist's public life and its historical context
- John's passage from Antiquities, XVIII, already quoted
- "After giving this account of John, in the same part of his work he [Josephus] goes on to speak as follows of our Saviour:"
- The Testimonium Flavianum, followed by Eusebius' comments:
- "When a historian sprung from the Hebrews [Josephus] has furnished in his own writing an almost contemporary record of John the Baptist and our Saviour too, what excuse is there left for not condemning the shameless dishonesty of those who forged the memoranda blackening them both?"
HC, I, 12: again, about the disciples/apostles (presented as the early transmitters of the Christian doctrine) and then, the Saviour's alleged resurrection and apparitions to them
HC, I, 13: the highly dubious exchange of letters (quoted later) between the king of Edessa and Jesus, allegedly right before the crucifixion. This is followed by the story of Thaddaeus, set after Jesus' death. Then:
HC, II, introduction:
"... Let us now in the present book [Book II of 'The History of the Church'] inquire about the events following his ascension ..."
That's it for Jesus' public life: only a few lines!

Note: in the same book, the description of Herod the Great's last months is more than five times longer.

And a few years prior to the publication of 'The History of the Church', Eusebius introduced the same TF in his 'Evangelical Demonstration' (ED) (published before 311), as follows:
"Certainly the attestations I have already produced concerning our Savior may be sufficient.
[certainly not! There is no other detailed and/or favourable external evidence in his 'The History of the Church', except for the widely discredited Abgar-Jesus letters]
`... However, it may not be amiss, if, over and above, we make use of Josephus the Jew for a further witness; who, in the eighteenth book of his Antiquities, when he was writing the history of what happened under Pilate, makes mention of our Saviour in these words:"

Notes:
a) Eusebius knew about 'Antiquities' and that Josephus wrote on "what happened under Pilate".
b) The expression "when he was writing the history of what happened under Pilate ..." does not pinpoint a precise position for the Testimonium, but just delimit the logical chronological "window" for it. Eusebius knew through the gospels that the public life of John the Baptist and Jesus happened during Pilate's rule. And even if Pilate is gone back to Rome at the end of Ant., XVIII, IV, 2, the next six sections, up to John's passage included, describe events happening ("under Pilate") before his departure.

Following this first (ever) quotation (and mention) of the TF, the comments of Eusebius are interesting:
"If, therefore, we have this historian's testimony, that he [Jesus] not only brought over to himself the twelve apostles, with the seventy disciples, but many of the Jews, and many of the Gentiles also, he must manifestly have had something extraordinary, above the rest of mankind; for how otherwise could, unless he performed admirable and amazing works, and used a method of teaching that was not common?"

Comments:
a) Here, the basis of the comment is Jesus attracting to him many people. Nothing else from the TF is used. This proves that, even expurgated, a Testimonium would have been of great benefit for the many Christian apologists before Eusebius' times (but none of them mentioned it!). This is confirmed by the Christian author Isidorus Pelusiota who commented, right after having quoted the TF:
"Now I cannot but wonder greatly at this great man's love of truth in many respects, but chiefly where he [Josephus] said, "Jesus was a teacher of men who received the truth with pleasure"" (The Scholar of Chrysostom, lib. IV, epist. 225, written around 410)
Despite this evidence, many proponents of the Testimonium contend that an expurgated TF had no value for Christian apologists, not worth to be quoted or even mentioned by them.
b) As if it were a trial run, Eusebius is very cautious about taking advantage of the TF. He deducted that Jesus must have "performed admirable and amazing works" because "he draw so many of the Jews and of the Gentiles" when he could have quoted (or at least brought about to "prove" his point), from the same TF, "he was a doer of wonderful works".
He is also tentative about Josephus, introduced as just "Josephus, the Jew" (before the TF quotation) and mentioned after plainly as "this historian".
Of course, that will all change a few years later, when Eusebius wrote 'The History of the Church' and grew bolder & more confident! Here, he put the TF on center stage and described Josephus as such:
"Of the Jews of that time he was the most famous, not only among his fellow-countrymen but among the Romans too ..." (HC, III, 9)

3. Did an authentic Testimonium Flavianum ever existed?

There are many reasons to doubt there was a Jesus' passage written by Josephus because:

3.1. All parts of the Testimonium are suspect:

Let's go back to the first Testimonium and examine it critically:

"Now there was about this time Jesus, a wise man, if it be lawful to call him a man;
[suggestion that Jesus was more than a man!]
` for he was a doer of wonderful works,
[suggestion that Jesus was more than a healer! "doer of wonderful works" hints to such things as the miraculous feedings. Also let's notice that 'for' (because) cannot refer to only "wise man": "doer of wonderful works" is not required in order to be a "wise man"! Evidently 'for' is related to what immediately precedes it, a hint of Jesus' divinity.
Note: Origen (3rd century) in "Contra Celsus", a well known work in Christiandom, mentioned "wonderful works" by Jesus four times: ch. VI, L, XLII & XLIX]

` a teacher of such men as receive the truth with pleasure.
[was Josephus (a fervent Jew) so isolated in Rome & consequently not knowing about some unJewish Christian beliefs? And then gave a boost to the new sect by vouching for the "teaching" of the alleged founder? Let's be realistic. Furthermore, Josephus, living more than one generation after, could not have known first hand what Jesus taught. And without a description of the "teaching" in the TF, that looks more like a blanket endorsement of the sayings, parables and discourses in the gospels!]

` He drew over to him both many of the Jews and many of the Gentiles.
[the gospels do not state Jesus attracting Gentiles and Paul suggested that Jesus dealt with Jews only:
Ro15:8a "For I tell you that Christ has become a servant of the Jews on behalf of God's truth, ..."
Gal4:4b-5a "[Jesus], born of a woman ... to redeem those under law [Jews] ..."
This embellishment above the gospels suggests a dating for this passage well beyond them (or Josephus was ill-informed!)]

` He was [the] Christ.
[the past tense in "was" would accommodate the fact that Josephus, as a non-Christian Jew, could not believe in a dead Messiah. Therefore "Christ" relates to the alleged perception about an alive (on earth!) Jesus, in the past. But could someone who died long ago still be thought to have been Christ when alive? Not, as it seems, for regular Jews, according to Paul in 1Co1:23 "... Christ crucified, a stumbling block to Jews ..."!
"He was [the] Christ" and its context have similarities with "... this man was the Son of God!" (Mk15:39), allegedly said by a non-Christian (a centurion), after Jesus' death (note: both "was" are in the same Greek tense: imperfect).
Also let's notice "Christ" ('Christos'), not "Messiah" (as in Jn1:41,4:25), as written in some biased translations.
Some scholars have proposed that "he was believed to be [the] Christ" is authentic: more later]

` And when Pilate, at the suggestion of the principal men amongst us, had condemned him to the cross,
[why would the Jewish establishment (to whom Josephus belonged!) want such a good and extraordinary man executed? No reasons are provided; this would be unprecedented for Josephus, who simply had to explain it, and more so because of the oddity of the situation: the Jewish leaders sending to the cross (as a rebel/criminal) a popular teacher of truth! Certainly, Josephus gave reasons for the executions of John the Baptist (emphatically) and James, the brother of Jesus. Also, he always indicated why other Jews were getting into any kind of troubles. But, for a Christian interpolator, the gospels and some N.T. epistles state why Jesus was crucified! No need for "Josephus" to provide explanations!]

` those that loved him at the first did not forsake him
[this is not according to Mk14:27, Mt26:31 & Jn16:32a "But a time is coming, and has come, when you will be scattered, each to his own home. You will leave me all alone.", where the opposite is allegedly prophesied by Jesus]

` for he appeared to them alive again the third day; as the divine prophets had foretold these
[the "prophets" never predicted a resurrection on the third day. The probable reference is the (far-fetched!) 'sign of Jonah' as appearing only in Mt12:40 (three days and three nights in the huge fish!).
Also, the wording is paraphrasing a combination of:
1Co15:4 "he was raised on the third day according to the scriptures"
Ac1:3a "After his suffering, he showed himself to these men and gave many convincing proofs that he was alive."
Justin Martyr (around 150), 'dialogue with Trypho', XVII:
"... Jesus was risen from the dead, ... as the prophecies did foretell ..."
Of course, Josephus, as a non-Christian, could not have related any resurrection of Jesus. Furthermore Josephus believed, and other Pharisees then, in reincarnation and immortality of the soul (as Philo of Alexandria), but not physical resurrection (Wars, II, VIII, 14; Ant., XVIII, I, 2)]

` and ten thousand other wonderful things concerning him.
[another blatant embellishment above the gospels (or even the scriptures). That could not have been written by a non-Christian]
` And the tribe of Christians, so named from him, are not extinct at this day."

Notes:

a) Overall, the Testimonium appears to be very much inspired by the "best" parts of the gospels. It seems to be a "reader digest" highly concentrated version, with further embellishments and claims. And, as I explained already (more to come), the alleged additions not only fit well into the so-called expurgated version, but seem to be entwined into it. Also noticeable is the (psychologically correct!) graduation of claims, from "a wise man", through "he was Christ" and finally to the resurrection.

b) Some scholars noticed that some of the words and expressions are also found in other parts of Josephus' works. But on such a short passage, that was easy to imitate for anyone familiar with the Jewish historian's books. In about 860, Photius wrote:
"which things may perhaps raise a doubt in some, whether Josephus was the author of this work,
['concerning Hades', actually written by Hippolytus of Rome (early 3rd century): explanation later in same Section C)]
` through the phraseology does not at all differ from the man's other works."
Furthermore, the use of "wise man" (found in Ant., VIII, II, 7 for Solomon) and "doer of wonderful works" (used only for Elisha, Ant., IX, VIII, 6) can be considered suspicious:
Why would Josephus go out of his way to associate Jesus with Solomon and Elisha? And remember the exact words he used (incidentally) for them ten books earlier? However, using Josephus' vocabulary would be a prime consideration for any interpolator.
Furthermore, one can make a good case about Eusebius' wording & themes appearing in the Testimonium.
And it is thought by some the TF has similarities with:
Lk24:19b-20 "[comparable items in bold] ... He was a prophet, powerful in word and deed before God and all the people. The chief priests and our rulers handed him over to be sentenced to death, and they crucified him;"
which, of course, a later Christian interpolator would have known.

c) After such glowing statements about Jesus (Christ), the last sentence appears to be a "back to reality" item from the overly "Christian" TF, which was absolutely required: without it, the Testimonium could not have been believed as written by a non-Christian. It has Josephus, known to have been a lifelong Jew, appear to "miss" on the theological implications of the previously stated "historical facts" (especially the resurrection) about Christ; and consequently not become a Christian! Therefore, he would find surprising there were still followers called Christians (some sixty years after the crucifixion): it was understood any fellowship dissipates quickly once the founder is dead, as alluded to in Ac5:36-39.
Here, a point is made (allegedly a few years after the crucifixion) that, if a movement (plan, work) is started by a man (Judas & Theudas, who got executed later, as Jesus did), it will disappear soon after its founder's death. Then, in conclusion:
"for if this plan or this work is of men, it will come to nothing;"
However:
"but if it is of God, you cannot overthrow it; ..."
It seems the author of the Testimonium knew about 'Acts'.

d) A comment by Earl Doherty, which I share entirely:
"In the case of every other would-be messiah or popular leader opposed to or executed by the Romans, he [Josephus] has nothing but evil to say. Indeed, he condemns the whole movement of popular agitators and rebels as the bane of the century. .... And yet the 'authentic' Testimonium would require us to believe that he made some kind of exception for Jesus." The Jesus Puzzle, p. 210-211

e) If "He was believed to be the Christ" or "He was Christ" (the only occurrence of "Christ" in the TF) was NOT in the original Testimonium (as many proponents of the expurgated version think), how could Josephus have written, at the end of it,
"And the tribe of Christians, so named from him"
"him" implies that someone was named (not long) before. Who could he be? "Jesus" appears in the TF, however 'Christians' is not derived from 'Jesus' but from 'Christ'. Furthermore, if "Christ" was not in the TF, it would be rather stupid to signify 'Christians' is a derivation of 'Jesus'. Consequently, according to "Christians, so named from him", 'Christ' had to be written earlier, as in Justin's 1Apology, XII, "... Jesus Christ; from whom also we have the name of Christians ..."
For examples, this is what Josephus wrote in:
Ant., XVIII, II, 3 "And now Herod the tetrarch, who was in great favor with Tiberius, built a city of the same name with him, and called it Tiberias."
Wars, I, XXI, 7 "but the honor of the building he ascribed to Caesar, and named it Cesarea accordingly."
Ant., XVII, V, 1 "... the haven called Sebastus ['Sebastôi'], which Herod had built at vast expenses in honor of Caesar, called Sebastus
['Kaisaros kalei Sebaston'. 'Sebaston' is Augustus in Greek]"
Ant., XVIII, II, 1 "He ... called it [the city] Julias, from the name of the emperor's wife [named 'Julia' (Tiberius' wife)]"

Note: in Josephus' works, there are other examples where a place is named from the (then) emperor/Caesar/king (or his relative/wife) but without having his/her name repeated. However, a place named from a title is never said to be derived from the name of its bearer, such as 'Cesarea, named from Tiberius' (comparable to 'Christians, named from Jesus').
Ant., XVI, V, 2 "...this he [Herod the Great] named Antipatris, from his father Antipater. He also built upon another spot of ground above Jericho, of the same name with his mother [named 'Cypros'], ..., and called it Cypros. He also dedicated the finest monuments to his brother Phasaelus, ..., by erecting a tower in the city itself, ... , which he named Phasaelus, ..., and a memorial for him ..., because it bare his name ..."

The Roman historian Tacitus wrote:
"... Christians: these he punished exquisitely. The author of this name was Christ" (Annals, lib. XV, written about 110)

f) "He was believed to be the Christ"
This appears only in Jerome's Latin version of the TF, written some seventy years after 'The History of the Church'. Jerome's TF has also some other noticeable differences with Eusebius' one:
"... He had many followers, both of the Jews and of the Gentiles: he was believed to be Christ. And then by the envy of our principal men ... and other [here, Jerome dropped "ten thousand"] wonderful things concerning him ..."
But then, that should not be surprising: as previously mentioned, many early quotes of the TF are different from the one in 'Antiquities'.
Jerome deleted "ten thousand" but added up Jesus' death was caused "by the envy" of the "principal men" (providing a (much needed) reason for Jesus' crucifixion, as sketched before by Jerome: "Christ was slain by the Pharisees, on account of the greatness of his miracles).
That proves Jerome did more than just a translation and likely used the opportunity to remove "he was Christ" (and "ten thousand"), deemed highly suspicious. The replacement, "he was believed to be the Christ", was certainly more believable as being written by Josephus. And then, according to Wm. Whiston, and forty years earlier, another Christian father went a bit further, quoting a TF, which does not have 'Christ' in it:
Ambrose, or Hegesippus de Excid. Urb. Hierosolym, lib. ii. cap. 12:
"That there was at the time a wise man, if it be lawful to have him called a man, a doer of wonderful works, who appeared to his disciples after the third day from his death, alive again, according to the writings of the prophets, ... from whom began the congregation of Christians ...
[there is no mention here that 'Christians' is named from someone]" (complete quote later on this page)

3.2. As mentioned by Eusebius, the location is "telling":

"After giving this account of John, in the same part of his work he [Josephus] goes on to speak as follows of our Saviour: [the TF follows]"
It is unlikely that Josephus would have written about Jesus right after John's story, which was set out of chronological order. Josephus brought it up because:
"Now, some of the Jews thought that the destruction of Herod's army [in 36] came from God, and was very justly, as a punishment of what he did against John, that was called the Baptist; for Herod slew him ..."
Note: in 'Wars' written earlier, Josephus did not report on Herod's army defeat.

If there was an authentic Jesus' passage, it would have been located somewhere else.
Then why did Eusebius write that the Jesus' passage followed the one about John?

Eusebius was a learned bishop, probably the most influential Christian in his days. And by that time, Christianity had assimilated John the Baptist, who became an important "Christian" figure. Attacks against him were considered as being against Christianity. And of course, Eusebius knew about John's passage. He was also very familiar with Josephus' works which he quoted extensively in 'The History of the Church'.
The Testimonium Flavianum was then (and still now, for many Christian scholars), and by a lot, the earliest, the longest and the only (very) complimentary piece of external evidence about Jesus. It was treated by Eusebius as more important for the Christian cause than all the gospels put together. Then, why would Eusebius misplace the TF (and right after having reproduced John's passage word by word), as some scholars contend? Certainly anyone familiar with the TF knows its exact relative place in Josephus' work, and it is NOT after John's passage, but well before that.
I can see only two possibilities:
a) Eusebius' copy of 'Antiquities' had already been interpolated, with the TF inserted right after John's passage (see later for other likely insertions).
b) The TF came originally from a separate sheet (attributed to Josephus); then Eusebius would have placed it as into the gospel context: during Pilate's rule and with Jesus' ministry following John's one, which is described in the eighteenth book of 'Antiquities'.

A good reason to link the TF to John's passage is the later was believed to be authentic. Certainly Eusebius did associate the Testimonium very closely with John's account.
But later, with John's passage out of chronological order, it became obvious that the TF (if kept here) would look like an addendum to (the much longer) John's story (with Jesus consequent of the Baptist).

Therefore, and also as unintentionally "suggested" earlier by Eusebius in his 'Evangelical Demonstration', the TF was systematically inserted where it is found now.

Contemporary scholars are not putting any significance to the initial TF location as reported by Eusebius. They ignore the "problem" or seem totally unaware of it:
"the passage on Jesus is not adjacent to Josephus' account of John the Baptist, which is probably where a Christian scribe would have put it had he invented the entire paragraph." (Professor Sanders, 'The Historical Figure of Jesus', p. 50)
And they have difficulty to explain why the TF is not directly linked to any other events, as John's and James' passages are (respectively, the defeat of Antipas' army and the removal of a high priest). Actually the TF, as it stands now, appears awkwardly inserted on its own, between two much longer stories (in Ant., XVIII, III), as follows:
- The account of Pilate's repression against unarmed Jewish protesters ending by:
"there were a great number of them slain by this means [clubbing by Roman soldiers], and others of them run away wounded; and thus an end was put to this sedition."
- Then the TF and right after:
- "About the same time also another sad calamity put the Jews into disorder; and certain shameful practices happened about the temple of Isis that was at Rome."
The calamity originated with four Jews in Rome who financially abused a gullible Roman lady: that caused the banishment of all the Jews living in the city. This is introduced by the very long and detailed story about the sexual abuse perpetrated on aristocratic Paulina, a worshiper of Isis (about eight times longer than the complete TF!). This later account, which does not involve Jews, was likely included in order to state that other religious professionals (the priests of Isis) were also implicated into abusing a Roman lady, but in worse ways (but with no banishment of Isis' worshipers!). Then after this digression, Josephus went on:
"I now return to the relation of what happened about the Jews of Rome, as I formely told you I would."
At the end of it, Josephus lamented:
"Thus were these Jews banished out of the city by the wickedness of four men."
before going to the next story:
Ant. XVIII, IV, 1 "But the nation of the Samaritans did not escape without tumults."
However, the TF is not presented as a digression for a purpose, or a calamity for the Jews, and simply does not fit where it is now.
Note: the story about the four Jews and the one about Paulina do not involve Pilate.

But would the incorporation of the TF in Josephus' Antiquities be a problem?
At that time (4th cent.), Christianity was becoming the new state religion. From now on, the Christian authorities exercised considerable power and control. Considering the great importance given by Eusebius to the Testimonium, they (and any Christian copyist) would make sure that the new copies of Josephus' Antiquities were "complete" (and the old ones destroyed!). And they had time to do it: the earliest copy of 'Antiquities' in our possession is dated eleventh century.
Note: "That Christian writers did in fact interpolate the works of Josephus was shown about 100 years ago when fifteenth-century manuscripts of a Russian translation of his The Jewish War were discovered containing information about John the Baptist, Jesus, and his disciples." 'The Jesus Legend' by G.A. Wells

3.3. In Josephus' works, spurious insertions were made by zealous Christians:

Could some work, NOT by Josephus, be attributed to him later on by a zealous Christian? The answer is YES:
'The Complete Works of Josephus', translated by William Whiston A.M., published in 1737, incorporates an excerpt from 'Josephus' Discourse To The Greek Concerning Hades'.
"In fact the passage belongs to a work by Hippolytus of Rome [Christian theologian and writer, early third century] entitled "Against the Greeks and Plato and on the Universe". The work is lost except for a rather lengthy fragment preserved in John of Damascus' Sacra Parallela which includes the excerpt on Hades and the comparison between Minos, Rhadamanthos, and Christ. The myth of Josephan authorship stems from Photius' Bibliotheca, which refers to a peri tou pantou of Josephus. However, Photius himself doubted the attribution to Josephus and cited a marginal note indicating a presbyter of Rome named Gaius as the author. As the marginal note claims that Gaius also wrote the Labyrinth which is another title for Hippolytus' Philosophumena, the gloss essentially got the authorship right, but confused the names Gaius and Hippolytus. The fragment is readily available on the Thesaurus Linguae Graecae cd-rom under Hippolytus, on the universe (around line 80)."
Matthew Kraus, Assistant Professor of Classics, Williams College

"Whiston (early 18th cent) could only argue for authenticity by virtue of his premise that Josephus was a Christian and became bishop of Jerusalem. That proposal has been thoroughly discredited"
Steve Mason, Academic Director, Centre for the Support of Teaching, 111 Central Square, York University, Toronto, Ontario.

Also, the same Whiston wrote, in Dissertation I of 'The Complete Works of Josephus':
"There are two remarkable passages in Suidas [about 980] and Theophylact [about 1080], already set down as citing Josephus: the former, "that Jesus officiated with the priests in the temple"; and the latter, that the destruction of Jerusalem, and miseries of the Jews, were owing to their "putting Jesus to death", which are in none of our present copies, nor cited thence by any ancienter authors, nor indeed do they seem altogether consistent with the other most authentic testimonies.
However since Suidas cites his passage from a treatise of Josephus, called "Memoirs Of The Jews' Captivity", a book never heard of elsewhere, and since both citations are not at all disagreeable to Josephus' character as a Nazarene or Ebionite [???], I dare not positively conclude they are spurious, but must leave them in suspense, for the further consideration of the learned."
Here, we can observe:
a) There were other spurious Josephus' passages about Jesus and even another (dubious) work attributed to the historian.
b) Whiston, an ardent Christian (and eminent mathematician & theologian, who succeeded Isaac Newton at Cambridge in 1703), was not outrightly rejecting them, despite his admission of the many indications of spuriousness.

3.4. Eusebius' record on spurious works is questionable:

In 'The History of the Church', Eusebius was prone to quote many items which now are generally considered spurious, such as:

a) Copy of a letter written by Abgar the troparch to Jesus and sent to him at Jerusalem by the courier Ananias
"Abgarus, ruler Of Edessa, to Jesus the excellent Saviour who has appeared in the country of Jerusalem, greeting.
I have heard the reports of you and of the cures as performed by you without medicines or herbs. For it is said that you make the blind to see and the lame to walk, that you cleanse lepers and cast out impure spirits and demons, and that you heal those afflicted with lingering disease, and raise the dead [according to the gospels!]. And having heard all these things concerning you, I have concluded that one of two things must be true: either you are God, and having come down from heaven you do these things, or else you, who do these things, are the Son of God. I have therefore written to you to ask you that you would take the trouble to come to me and heal the disease which I have. For I have heard that the Jews are murmuring against you and are plotting to injure you. But I have a very small yet noble city which is great enough for us both."
'The History of the Church', I, 13

Note: this letter and more so the Testimonium (and not the gospels) were used by Eusebius to provide most of the "information" about Jesus' public life. Obviously, Eusebius greatly appreciated helpful items of external evidence!

Jesus' alleged reply follows:

b) Jesus' reply to the troparch Abgar by the courier Ananias
"Blessed are you who have believed in me without having seen me.
[as the latter Christians! Likely drawn from Jn20:29b "blessed are those who have not seen and yet have believed."]
` For it is written concerning me, that they who have seen me will not believe in me, and that they who have not seen me will believe and be saved.
[again, allusion to the rejection by Jesus' contemporary Jews of Palestine and the conversion of Gentile Christians later on. And nothing of that sort had been written yet! The gospels and epistles were composed (well) after his death]
` But in regard to what you have written me, that I should come to you, it is necessary for me to fulfill all things here for which I have been sent, and after I have fulfilled them thus to be taken up again to him that sent me. But after I have been taken up I will send to you one of my disciples, that he may heal the disease and give life to you and your people."
'The History of the Church', I, 13

Notes:
a) Abgar is not a name but a title like Pharaoh or Caesar.
b) Eusebius wrote:
"King Abgar, the brilliantly successful monarch of the people of Mesopotamia"

Note: this is a gross exaggeration. Why?
The king of Edessa was ruling over a very small kingdom at the northern fringe of Mesopotamia. Most of this region was under Parthian control.
Certainly Eusebius was very complimentary about anyone (like Josephus also) who, long ago, allegedly wrote favorable testimonies about Jesus!

c) Eusebius declared:
"Written evidence of these things is available, taken from the Record Office at Edessa, at that time the royal capital. In the public documents there, embracing early history and also the events of Abgar's time, this record is found preserved from then until now: the most satisfactory course is to listen to the actual letters, which I have extracted from the archives and translated word by word from the Syriac as below: [as quoted above]"
d) These letters were not reported to be known before Eusebius quoted them.
e) After the two letters, Eusebius related a long follow-up story:
"To these letters is subjoined the following in Syriac:
After Jesus was taken up, Judas, also known as Thomas,
[mention of Thomas as Judas appeared not before the 2nd century]
` sent to him [Abgar] as an apostle Thaddaeus, one of the seventy ... the wonders he [Thaddaeus] performed ... [Thaddaeus] is performing many wonders ... a wonderful vision ... He [Jesus] was taken up ... performing many wonders ..."
Also here, it is reported that Jesus "was crucified and descended into Hades, ... and raised the dead; ... he descended alone, but ascended with a great multitude to his Father." Nothing of this sort is written in the New Testament! However that may be an "interpretive" extrapolation from a combination of Mt27:52-53, Lk16:22-24,23:43, 1Pet3:18-20, 'To the Magnesians' (9:2) (dated 125-145) and, more so, 'Ascension of Isaiah' (9:17) (dated 150-200).
Needless to say, nobody heard about this story before.

Eusebius was likely to add up on the work of other authors.

a) In his 'Evangelical Demonstration' Book III, after having cited the Testimonium and commented on it (as quoted earlier), Eusebius went on:
"Morever, the scripture of the Acts of the Apostles (xxi. 20.[Ac21:20] ) bears witness, that there were many ten thousands of Jews, who were persuaded that he was the Christ of God, who was foretold by the prophets."
But in Ac21:20, we read:
"When they heard this, they praised God. Then they said to Paul: "You see, brother, how many thousands of Jews [and NOT "many ten thousands ..."] have believed, and all of them are zealous for the law."
[the Torah; but no mention of these Jews seeing Jesus as "the Christ of God"!]"

b) In 'The History of the Church', II, 2, Eusebius declared:
"These things are recorded by Tertullian [160?-225?], a man well versed in the laws of the Romans, and in other respects of high repute, and one of those especially distinguished in Rome. In his apology for the Christians [Chapter V], which was written by him in the Latin language, and has been translated into Greek, he writes as follows:
"But in order that we may give an account of these laws from their origin, it was an ancient decree that no one should be consecrated a God by the emperor until the Senate had expressed its approval. Marcus Aurelius did thus concerning a certain idol, Alburnus. And this is a point in favor of our doctrine,
[also translated as "this reinforces my argument" (Penguin Classics translation)]
` that among you divine dignity is conferred by human decree. If a God does not please a man he is not made a God. Thus, according to this custom, it is necessary for man to be gracious to God. Tiberius, therefore,
[from now on, Tertullian appears to be extrapolating from his aforementioned legal, historical and philosophical observations. What follows is just wishful speculation, with the assumption Tiberius considered (dead) Jesus as a God]
` under whom the name of Christ made its entry into the world, when this doctrine
[it was way too early for any Christian doctrine!]
` was reported to him from Palestine where it first began, communicated with the Senate, making it clear to them that he was pleased with the doctrine.
[good advertisement for the doctrine! But such unusual actions would have been reported by Roman historians: not a trace. And our author was historically suspect: Tertullian had Pilate as "Roman governor of Syria" Apologia, ch. XXI]
` But the Senate, since it had not itself proved the matter, rejected it. But Tiberius continued to hold his own opinion, and threatened death to the accusers of the Christians.
[Christians were not even existing then. Furthermore the great persecution against the "Church of Jerusalem" (35C.E.), at the time the main "Jesus" community, occurred during Tiberius' reign (and Pilate's rule)]"

However, right before the quote from Tertullian's Apology, Eusebius gave his own version of "these things ... recorded by Tertullian" Let's notice the embellishments and additions:
"And when the wonderful resurrection and ascension of our Saviour were already noised abroad, in accordance with an ancient custom which prevailed among the rulers of the provinces, of reporting to the emperor the novel occurrences which took place in them, in order that nothing might escape him, Pontius Pilate informed Tiberius of the reports which were noised abroad through all Palestine concerning the resurrection of our Saviour Jesus from the dead.
[in the (inaccurate) Eusebius' quote of Tertullian's Apology, only a doctrine is reported to Tiberius. But Tertullian himself never wrote about a doctrine communicated from Pilate: "Tiberius accordingly, ..., having himself received intelligence from Palestine of events [unspecified! No mention of resurrection] which had clearly shown the truth of Christ's divinity"]
` He gave an account also of other wonders which he had learned of him, and how, after his death, having risen from the dead, he was now believed by many to be a God ..."

After the quotation from Tertullian's Apologia, Eusebius continued:
"Heavenly providence had wisely instilled this into his [Tiberius] mind in order that the doctrine of the Gospel, unhindered at its beginning, might spread in all directions throughout the world."
What follows is exhilarating, but historically unfounded (according to Paul's letters, 'Acts', the external evidence and Eusebius himself: see next note):
"Thus, under the influence of heavenly power, and with the divine cooperation, the doctrine of the Saviour, like the rays of the sun, quickly illumined the whole world; straightway [at once], in accordance with the divine Scriptures, the voice of the inspired evangelists and apostles went forth through all the earth, and their words to the end of the world. In every city and village, churches were quickly established, filled with multitudes of people like a replenished threshing-floor ... those whose minds ... were fettered by the ancient disease of idolatrous superstition, ... were ... through the teaching and the wonderful works of his disciples, set free"
This "over the top" declaration is very similar to the "too good to be true" Testimonium Flavianum.

Note: Eusebius wrote in 'The History of the Church', 3, 1:
"Such then was the plight of the Jews.
[events of 66, as reported in the preceding paragraph: HC, II, 26]
` Meanwhile the holy apostles and disciples of our Saviour were scattered [from Jerusalem] over the whole world.
[this alleged dispersion is not "straightway" but more than thirty years later!]
` Thomas, tradition tells us, was chosen for Parthia, Andrew for Scythia, ..."
And for Eusebius, the Gentiles' salvation began years after Jesus' death:
"But the divine grace being now poured out upon the rest of the nations. Cornelius, of Cesarea in Palestine, with his whole house, through a divine revelation and the agency of Peter, first received faith in Christ;
[according to Ac9-10, that was after Paul's conversion in 35]
` and after him a multitude of other Greeks in Antioch" (HC, II, 3)

And very likely, Eusebius used a blatantly "Christianized" copy of Josephus' Antiquities (either that or he was interpolating!):
In 'The History of the Church', II, 10, about the death of Agrippa I, Eusebius quoted Josephus "who clearly testifies to the truth in Antiquities Book XIX, where he tells us the amazing story in these words":
"... A moment later, he [Agrippa I] looked up, and sitting over his head he saw an angel ..."
An angel is featured in 'Acts':
Ac13:23 "Immediately, because Herod [Agrippa I] did not give praise to God, an angel of the Lord struck him down, and he was eaten by worms and died."
But in all the ancient copies of 'Antiquities', we read:
"But as he [Agrippa I] presently afterwards looked up, he saw an owl sitting on a certain rope over his head." (Ant., XIX, VIII, 2)

Eusebius was certainly not the one to reject Christian embellishments or harmonizations. And he generated some of those! For him, the more "too good to be true", the better.

As another example:
Hegesippus, a second century author (who did not appear to know about Josephus' works) and also a confirmed Christian "embellisher", wrote:
"Immediately after this [James' execution] Vespasian began to besiege them
[the people of Jerusalem; but that was eight years later!]"
'The History of the Church', II, 23
Of course, Eusebius was glad to accept the "information" and even embellish on it:
"After the martyrdom of James and the capture of Jerusalem which instantly followed ..."
'The History of the Church', III, 11
But Eusebius knew about the eight years difference. After quoting Josephus on the passage about James' execution (HC, II, 23), he went on:
"In the eighth year of Nero's reign ... [61-62]" (HC, II, 24)
After that, Eusebius commented on Nero's persecutions (64), then the trouble in Palestine starting under Florus "in the twelfth year of Nero's reign [65-66]" (HC, II, 25-26), to arrive finally to the time of Vespasian:
"When Nero had been master of the empire for thirteen years, the business of Galba and Otho occupied a year and a half [68-69]; and then Vespasian ...
[successfully fought against the Jews, "was proclaimed emperor while still in Judea"]" (HC, III, 5)

PS: on the subject of Eusebius, from an article about the shroud of Turin in my newspaper (dated April 13th, 2001), I quote:
"In fact, said Whanger [Dr. Whanger is a retired medical professor and a methodist], the ancient historian Eusebius, examined the city records of Edessa, and found that its king Abgar IV, the church's first official convert, received what was described as Christ's burial shroud from the apostles themselves in 30 AD."
This is a reference to Eusebius' 'The History of the Church', the alleged letters of Jesus and Abgar, and, more so, the follow-up document about Thaddaeus' trip to Edessa. However:
a) Eusebius is mostly a bishop and a Christian apologist, whose works, as we examined, are full of misquotes, proven embellishments and dubious "new" evidence.
b) He does not name "Abgar IV", just "Abgar".
c) Nowhere it is said the king became a convert. He is certainly most amazed at Thaddaeus' wonderful works, calls Jesus "Son of God", but conversion or baptism: NO mention.
d) Only Thaddaeus (an alleged member of the seventy, not the twelve) goes to Edessa, not the apostles (plural).
e) There is no mention he brought anything with him, NO shroud!
Unfortunately, this kind of use of (pseudo) history (and also pseudo sciences) is prevalent from zealous people. And what is happening today (and likely tomorrow) is not new!

From the same article, Dr. Whanger claims to have seen on the shroud "an amazing amount of surface details, like hundreds of flowers", "two coins on the eyes - the right one is clearer - they're Jewish pennies called piutah, minted in AD 29. ...". However, Barrie Schwortz, another ardent believer in the authenticity of the shroud, could not confirm that from high resolution photographs, not even the presence of coins: http://www.shroud.com/faq.htm#3

3.5. Prior to Eusebius, the Testimonium Flavianum was not known:

Origen's assertions (about Josephus "who did not receive Jesus for Christ") could have been partly based on the spurious insertion about James and Josephus' Ant., XX, IX, 1.
There, "Jesus, who was called Christ", could be interpreted as if Josephus did not consider Jesus as being the Christ.
But even more plausible, is that Josephus, well known for his defense of the Jewish cause in all his works, stayed a Pharisaic Jew all his life. Consequently Origen could have drawn from this undisputed fact that Josephus was not a Christian, not even a Jewish Christian, and, of course, "did not believe in Jesus as Christ."
Therefore, the existence of an expurgated Testimonium is not necessary in order to explain that, from Origen's perspective, Josephus did not see Jesus as the Christ.
As I noted before, the TF, even expurgated of "Jesus was Christ", his resurrection and other things, is very complimentary about Jesus. Certainly, with "a wise man", "for he was a doer of wonderful works", "a teacher of such men as receive the truth with pleasure", "He drew over to him both many of the Jews and many of the Gentiles" and with or without "He was believed to be the Christ", Origen could have easily made a case that Josephus was a "closet" Christian or at least, an admirer of Jesus. He did not and there is no evidence that Origen used any part of the TF in his works.

Remark: the same goes for all Christian writers up to Eusebius, many of them apologists, who could have used a "decent" Testimonium Flavianum in their defence of Jesus and Christianity: not a trace of it!

Notes:
a) Irenaeus, the very influential bishop of Lyons at the end of the second century and a prolific author, knew about Josephus and 'Antiquities':
"Josephus says, that when Moses had been brought up in the royal palaces, he was chosen as general against the Ethiopians;"
"Lost Writings", XXXII
b) Clement of Alexandria, a contemporary of Irenaeus, and also an author,
"who cites the Antiquities of Josephus but never cites the testimonies now before us ..."
Wm. Whiston, 'The complete work of Josephus', Dissertation I, XI
c) "Fieldman names two Fathers from the second century, seven from the third, and two from the early fourth, all of whom knew Josephus and cited from his works, but "do not refer to this passage [the TF] ..." (Josephus, p. 695)" 'The Jesus Legend', G.A. Wells

3.6. In 'Antiquities', any previous mention of "Jesus" or "Christ" is not required:

Let's start by these two observations:
a) Wars, VI, VIII, 3 "... one of the priests, the son of Thebuthus, whose name was Jesus ..."
This is the only mention of "Thebuthus" in 'Wars'.
b) Wars, II, XII, 8 "he had also another daughter by Petina, whose name was Antonia."
This is the only mention of "Petina" in "Wars". Petina was the second wife of Claudius (he went through four of them).
c) Wars, II, XII, 8 "After this Caesar sent Felix, the brother of Pallas, to be procurator of Galilee, and Samaria, and Perea ..."
This is the only mention of "Pallas" in 'Wars' (the 'Pallas' in Wars I, XXVIII, 8 is another person, the mother of one of Herod the Great's son), but is known to us through other historical records: he was a favorite in the court of Claudius, then the one of Nero. Because procurators/prefects/governors are rarely identified with father or brother in Josephus' works, the mention of Pallas can be explained because the historian felt like it!
Let's also note there is another 'Felix' in 'Wars' (I, XII, 1), a Roman commander who lived three to four generations earlier, but appears only one book before.

According to these observations, Josephus may NOT have mentioned "Jesus, ... Christ" before:
Ant., XX, IX, 1 "... the brother of Jesus, who was called Christ, whose name is James ..."

Next, I'll try to demonstrate that Josephus' potential readers were aware about Christians and their name's origin: Christ or 'Christus' (as written in Latin by Tacitus and Pliny).
It was around 93, at a time when Christianity had already spread considerably, especially in Rome:
"but the pernicious superstition [Christianity], repressed for a time broke out again, not only through Judea, where the mischief originated, but through the city of Rome also, where all things hideous and shameful from every part of the world find their center and become popular [the author hated Christians & Christianity]."
(Tacitus' Annals, lib. XV)
In the same book, about the horrific persecution of the Christians by Nero in 64, Tacitus wrote:
"Hence, even for criminals who deserved extreme and exemplary punishment,
[another expression of hate against Christians. However, Tacitus never accused the Christians of arson]
` there arose a feeling of compassion;
[paving the way for a later rebirth of a strong and influential Roman Christian community, as attested by the 1Clement epistle]
` for it was not, as it seemed, for the public good, but to glut one man's cruelty [Nero's one], that they were being destroyed.
[as scapegoats. It looks these unfortunate Christians were remembered]"
The execution of these Christians was closely associated with one of the worst disaster of Rome's history: the loss of many lives in the great fire (which lasted more than five days) and the near complete destruction of almost three quarters of the city, with irreplaceable monuments and art works, certainly something to be remembered some thirty years later.
Note: for more than twenty years, Josephus had settled in Rome. As I will explain later, he was not concerned about Christians and had no reason to do any research on them. Consequently, his perception of what his readers would know about Christians and Christ has to be understood into a city of Rome's context.

If the Christians, according to Tacitus' testimony, were known in Rome, would the Romans be unaware that the name comes from "Christ"?
Does anyone who knows about "Buddhist" can be ignorant that the name is derived from a certain "Buddha"?
Also, Tacitus' mention of "the author of this name [Christians] was Christ" should not be construed as his desire to educate ignorant people. Tacitus, as an historian, passed on pieces of data, as he knew it, without worrying if they were already common knowledge or not. Furthermore, the aforementioned statement is no more that a link in the narration:
"Nero, in order to stifle the rumor ascribed it to those people who were hated for their wicked practices, and called by the vulgar, Christians: these he punished exquisitely. The author of this name was Christ, who, in the reign of Tiberius, was brought to punishment by Pontius Pilate, the procurator.
[Tacitus seems to justify Nero's actions against Christians by what Pilate did on their alleged founder]
` But the pernicious superstition, repressed for a time broke out again, not only through Judea, where the mischief originated, but through the city of Rome" (Annals, lib. XV)

Notes:
a) Tacitus mentioned "superstition" without indicating what it consisted of, except that it was pernicious.
b) At about the same time, Pliny the Younger, in a letter to Emperor Trajan, also described Christian beliefs as being a (bad and extravagant) superstition, without giving any more details. Pliny must have known that Trajan was aware of the nature of that "superstition" (as for any other Romans). Certainly, Pliny, who interrogated Christians and ex-Christians (without extortion), could have got the information from them and supplied Trajan with it. Pliny did not.
Also, Pliny mentioned 'Christ' three times without giving any further identification, except that "Christ" was treated as a god: "to sing a hymn to Christ, as to a god". Once again, it is obvious that Pliny did not think the emperor was in need of explanations.

PS: the same Pliny was aware of Christians, even of examination of Christians by others:
"I have never been present at a formal inquiry of Christians. Consequently, I do not know the nature or the extent of the sanctions usually administered against them, nor the grounds for opening a formal inquiry and how far it should be pressed."

In conclusion, it is likely that Josephus, working around 93 in a Roman environment, would perceive that his future readers knew already about "Christ", at least as the (alleged) originator of the Christian sect, with no prior Jesus/Christ's passage required and no further details to be added.

But why did Josephus name Jesus in the first place (Ant., XX, IX, 1)?
The answer is simple: there were many 'James' then, and he had to be identified. But how? Well, his brother was known as "called Christ" (around 93 in Rome) and the alleged founder of a new sect/religion. So "brother of Jesus, who was called Christ"
Also, Josephus might have taken pleasure to associate Jesus "called Christ" with his own brother accused of breaking the Law (Ant., XX, IX, 1, see later in next Section). Let's notice that "Jesus, who was called Christ" is placed in evidence before "James". This construction is not unique in Josephus' works but certainly unusual:
Wars, II, XXI, 1 "a man of Gischala [Galilee], the son of Levi, whose name was John [a Zealot leader]."
Wars, VI, VIII, 3 "one of the priests, the son of Thebuthus , whose name was Jesus ..."
Ant., XX, V, 1 "the sons of Judas of Galilee [a rebel: more later] were now slain; ... The names of those sons were James and Simon, whom Alexander commanded to be crucified"

3.7. Josephus did not care about Christians (and consequently Jesus):

Josephus, as a Jew, was not likely to elaborate on the alleged originator of a new religion which was, by then, expanding and competing with Judaism for new converts. That seems to be confirmed by his treatment of James' trial and stoning in Ant., XX, IX, 1. Here, James is named only once, with no mention of his significance or character (in sharp contrast with Josephus' rendering of John the Baptist):
"But this younger Ananus, who, as we have told you already, took the high priesthood, was a bold man in his temper, and very insolent; he was also of the sect of the Sadducees, who are very rigid in judging offenders, above all the rest of the Jews,
[Josephus' indication is that the offenders (like James) did break the Law but not by much. The offences they committed were tolerated by the other Jews. Josephus seemed to have known more about the charge against James (and his offence) than he was telling!]
` as we have already observed; when, therefore, Ananus was of this disposition, he thought he had now a proper opportunity. Festus was now dead, and Albinus was but upon the road;
[Ananus knew that no Roman governor would have authorized the trial]
` so he assembled the sanhedrim of judges, and brought before them the brother of Jesus, who was called Christ,
["Jesus the said Christ" (iesou tou legomenou christou): 'Christ', not 'Messiah' as written in some other (inaccurate) translations]
` whose name was James, and some others;
[probably members of the "Nazarene" community: same offence, same trial and same proposed condemnation]
` and when he had formed an accusation against them as breakers of the law, he delivered them to be stoned."
Josephus went on to declare:
"but as for those who seemed the most equitable of the citizens, and such as were the most uneasy at the breach of the laws,
[civil laws, not the Torah (Mosaic Law): see next note]
` they disliked
["was heavy for them to bear." (bareOs Enenkan epi toutOi) but not "were deeply shocked" as written in some (biased) other translation]
` what was done: they also sent to the king [Agrippa II], desiring him to send to Ananus that he should act so no more [James' life sounds rather cheap!], for that what he had already done was not to be justified:
[again, no sign of outrage about James' execution, of which Josephus did not bother to confirm]
` nay, some of them went also to meet Albinus ..."
Josephus was rather casual and showed no compassion for James in the whole affair, which, as a young Jewish priest (and living in Jerusalem at the time), he would have heard about, and possibly witnessed. Finally, it appears the whole episode was mostly written in order to explain the replacement of a high priest (in 'Antiquities', Josephus gave a lot of importance to the high priests and their succession), and not to narrate James' trial and death by stoning, mentioned here in a few words only.

Note: the nature of the (civil) laws being breached is explained by Josephus in the same passage:
"nay, some of them went also to meet Albinus [the new Roman procurator], as he was upon his journey from Alexandria, and informed him that it was not lawful for Ananus to assemble a sanhedrim without his consent.
[again, no concern about the executions of James and the others; just objection against legal irregularities]
` Whereupon Albinus complied with what they said, and wrote in anger to Ananus, and threatened that he would bring him in punishment for what he had done: on which king Agrippa [II] took the high priesthood from him ..."

Josephus wrote compassionately about the Jews (even Samaritans who according to Ant., XVIII, IV, 1, are considered to be from a different nation than the Jews!) living in Palestine and from all over the known world.
"... I began to write that account of the war; and these Antiquities contain what hath been delivered down to us from the original creation of man, until the twelfth year of the reign of Nero [65-66], as to what hath befallen the Jews, as well in Egypt as in Syria and in Palestine, and what we have suffered from the Assyrians and Babylonians, and what afflictions the Persians and Macedonians, and after them the Romans, have brought upon us" (Ant., XX, XI, 2)

The plight of his contemporary Jews living in cities like Jerusalem, Babylon, Antioch, Alexandria, Cyrene and Rome attracted his attention. He went out of his way to narrate their sufferings, persecutions and crises. However, there is nothing in his works about "Nazarenes" or Christians, not even Nero's persecution in 64, known to us mostly by Tacitus:
"Accordingly, an arrest was first made of all who pleaded guilty; then, upon their information, an immense multitude was convicted, not so much of the crime of firing the city, as of hatred against mankind. Mockery of every sort was added to their deaths. Covered with the skins of beasts, they were torn by dogs and perished, or were nailed to crosses, or were doomed to the flames and burnt, to serve as a nightly illumination, when daylight had expired." (Annals, lib. XV)
In Ac12:1-19, king Agrippa I is seen persecuting the members of the "Church of Jerusalem" (around 42)
"He had James, the brother of John, put to death with the sword. When he saw that this pleased the Jews, he proceeded to seize Peter also." After the escape of Peter from jail, "he [the king] cross-examined the guards and ordered that they be executed."
There is no mention of that in Josephus' works and he described Agrippa and his short reign in the best terms:
"He was in like manner rather of a gentle and compassionate temper." (Ant., XIX, VII, 3)
And of course, in Josephus' works, we have nothing about the great persecution against the "Church of Jerusalem" in 35, the one in which Paul participated.

Josephus, because he was a Jew and whatever other reasons, gave the silent treatment to the Christians. Therefore, it should not be surprising that, in all likelihood, he never wrote a Jesus' passage.

And then, why would Josephus describe Jesus very sympathetically when he was so apathetic and brief concerning his brother James & execution?

3.8. Another Jewish historian and contemporary of Josephus, did not include Jesus in his works:

Justus, from Tiberias in Galilee, was well known by Josephus, as a personal enemy (reference: Josephus' Life, 65). He wrote a Jewish history (now disappeared) covering the reigns of the Herodian kings. This is what Phoetus (around 860) reported:
"I have read the Chronicles of Justus of Tiberias. He omits the greatest part of what was necessary to be related; but, as infected with Jewish prejudices, being himself a Jew by birth, he makes no mention at all of the advent, or of the acts done, or of the miracles wrought, by Christ."

3.9. The author of a spurious insertion did not know any Testimonium Flavianum:

As already mentioned, the spurious insertion about James in 'Antiquities' features:
"brother of Jesus who was called Christ"
This is obviously drawn from Josephus:
"brother of Jesus, who was called Christ"
And the latter Christian author who inserted the second James' passage was prone to embellish upon what Josephus wrote:
"James" (Ant., XX, IX, 1)
became in the spurious passage:
"James the Righteous, ... , who was a most righteous person."
Then, if our latter author was so inclined to embellish, why did he not draw his reference of Jesus as Christ from "He was Christ" or "He was believed to be the Christ" and "improve" on it?

Note: some scholars nowadays believe that the "spurious" James' passage is authentic. I object to that. But first, let's requote the passage in question:
"these miseries befell the Jews by way of revenge of James the Righteous, who was the brother of Jesus who was called Christ; [because they had slain him], who was a most righteous person." (Eusebius, HC, II, 23)
Here are the reasons for my rejection:
a) Similarity of wording in Hegesippus (mid-2nd cent.) account of James' death:
"James ... whom everyone ... has called the Righteous ... Because of his unsurpassable righteousness he was called the Righteous ..." HC, II, 23.
Also, this author may have prompted the spurious James' passage when he wrote:
" ... after this [James' execution] Vespasian began to besiege them
[the people of Jerusalem. But that happened some eight years later!]" (HC, II, 23)
b) In Ant., XX, IX, 1, and as mentioned before, neither Josephus, nor "the most equitable of the citizens", are outraged by the executions of James and the "others" (and no reaction of the population is reported then). The "citizens" (and the new Roman governor) are only concerned about the breach of civil laws, making the life of the executed ones rather "cheap".
James' trial and execution are of little consequence: they cause only the removal of a high priest. They are brought about and narrated (very briefly I may add) in order to explain the change in the high priesthood, a subject very dear to Josephus in 'Antiquities'. Also here, he took great pain to relate the efforts of "the most equitable of the citizens" against a breach of the Roman (civil) laws, likely in order to stress there were still "good" people in Jerusalem then.
In conclusion, James' execution, by itself, is treated so insignificantly that, from Josephus' point of view, (divine) revenge against the Jews could not be attributed to it.
c) In Ant., XX, IX, 1, nothing is said about James' character. Why, at James' alleged second mention, would Josephus suddenly rave about him?
"James the Righteous, ... , who was a most righteous person"
d) From 94 to 320, out of the eleven Christian writers quoting Josephus' works, only Origen related James' second passage.

3.10. Josephus' Antiquities lacks the reference of a prior Jesus' story:

Now let's look at one example in Josephus' work, where one man (of significance) is mentioned, again and again, in relation to kins. Let's try to identify a pattern, shall we?
Josephus first mentioned Judas of Galilee as:
Wars, II, VIII, 2 "Under his administration, it was that a certain Galilean, whose name was Judas, prevailed with his countrymen to revolt; and said they were coward if they would endure to pay a tax to the Romans, and would, after God, submit to mortal men as their lords."
Nine chapters later, in Wars, II, XVII, 8, the next reference to Judas occurs as follows:
"In the meantime one Manahem, the son of Judas, that was called the Galilean (who was a very cunning sophister, and had formerly reproached the Jews under Cyrenius, that after God they were subject to the Romans)"
Here, Josephus repeated Judas' exhortations in some details.
Five books later, in Wars, VII, VIII, 1, the next reference to Judas is:
"... Eleazar, a potent man, and the commander of these Sicarii, that had seized upon it. He was a descendant from that Judas who had persuaded abundance of the Jews, as we have formerly related, not to submit to the taxation when Cyrenius was sent into Judea to make one; ..."
A blatant indication by Josephus that he already wrote about Judas and his exhortation for revolt.

In 'Antiquities', Josephus reintroduced Judas and his revolt in a lot of details:
Ant., XVIII, I, 1 "Moreover, Cyrenius came himself into Judea, which was now added to the province of Syria, to take an account of their substance, and to dispose of Archelaus' money; but the Jews, although at the beginning they took the report of a taxation heinously, yet did they leave off any further opposition to it, ...
Yet was there one Judas, a Gaulonite, of a city whose name was Gamala, who, taking with him Sadduc, a Pharisee, became zealous to draw them to a revolt, who both said that this taxation was no better than an introduction to slavery, and exhorted the nation to assert their liberty;"
Two books later, Josephus mentioned Judas again:
Ant., XX, V, 1 "the sons of Judas of Galilee were now slain; I mean that Judas who caused the people to revolt, when Cyrenius came to take an account of the estates of the Jews, as we have shown in a foregoing book. The names of those sons were James and Simon, whom Alexander commanded to be crucified"
The pattern is very obvious: when Josephus wrote about Judas again, a significant amount of identifying details is always repeated. Also, if the previous mention of Judas is not in the same book, Josephus indicated that the Judas' story has been narrated earlier.

However, "Jesus, who was called Christ":
a) Does not include any reference that the Jesus' story has already been described (allegedly two books earlier).
b) Does not incorporate any associated details (other that the identifier, "called Christ"; as for Judas of Galilee/Gamala) from the Testimonium Flavianum, such as:
- Crucified by Pilate
- "wise man"
- "doer of wonderful works"

Notes:
a) In 'Wars', the first mention of Judas comes with 'Galilean'. In 'Antiquities', the story of Judas includes "a Gaulonite, of a city whose name was Gamala," and the name of his main follower "Sadduc, a Pharisee".
There is no detail of this kind (like Galilee, Nazareth, Capernaum, Jerusalem, Peter) in the Testimonium. Actually, there is no geographical reference at all in the TF (making Jesus very universal!).
Note: in John's passage there is only one place being named (Macherus) but 'Herod' appears five times.
b) The first reference of Judas in each work comes with an explanation about Judas' main message:
Wars, II, VIII, 2 "... Judas, prevailed with his countrymen to revolt; and said they were coward if they would endure to pay a tax to the Romans, and would, after God, submit to mortal men as their lords."
Ant., XVIII, I, 1 "Judas, ... became zealous to draw them to a revolt, ... said that this taxation was no better than an introduction to slavery, and exhorted the nation to assert their liberty
In John's passage, Josephus also wrote about the Baptist's message:
Ant., XVIII, V, 2 "... John, ... commanded the Jews to exercise virtue, both as righteousness towards one another, and piety towards God, ..."
In the Testimonium, there is no description of Jesus' message.

4. Conclusion:

In all likelihood, Josephus never wrote any Testimonium Flavianum.
Many liberal Christian scholars (and other ones) have accepted the existence of some expurgated "authentic" TF (but not necessarily the same one!), justifying their opinions by delicate one-sided argumentation. However, that should not be surprising, considering the (expurgated or not) Testimonium would be:
a) one among two or three least disputed items of external "proof" about Jesus' existence
b) the only piece of external evidence about Jesus which is favourable to him
c) the most detailed one
d) a passage which stresses Jesus as a popular sage/wise man, now the focus of many scholarly "studies" about the "historical Jesus"

5. Sequence of spurious insertions in Josephus' works:

Let's now recapitulate about the likely sequence and reasons for the spurious insertions in Josephus' Antiquities:

5.1. Josephus' Antiquities came out (93-94) with only John's passage (XVIII, V, 2) and James' trial (XX, IX, 1).

5.2. Because Josephus indicated that Jews thought that Herod Antipas' army destruction had been caused by God as a punishment for John the Baptist's execution, a Christian copyist added (150?-220?), at least on a few copies, the now disappeared spurious passage (acknowledged by Origen and Eusebius) about James' execution starting troubles for the Jews. And it is likely that James' execution, and not Jesus' own, was selected because there was no TF at the time.

5.3. These passages, in turn, caused the comments from Origen (230-250).

5.4. Another Christian author then drafted up the famous Testimonium Flavianum (250?-310?) for obvious reasons:

A) Fill up a big hole in Josephus' works, especially when the Jewish historian wrote a very complimentary account of John the Baptist (note: John's passage is about twice as long as the complete TF).
The "Christianization" of 'Antiquities' allowed Eusebius to use extensively Josephus' works, as he did in 'The History of the Church'. And after Eusebius, and within the next ninety years, the Testimonium and Josephus were prominently mentioned by some (but not most) Christian apologists of these times (reference: Wm. Whiston, Appendix, Dissertation I)

a) About 360: Ambrose, or Hegesippus de Excid. Urb. Hierosolym, lib. ii. cap. 12
The quotation of the (greatly modified) TF is introduced and narrated as:
"The Jews themselves also bear witness to Christ, as appears by Josephus, the writer of their history, who says thus:
"That there was at the time a wise man, if it be lawful to have him called a man, a doer of wonderful works, who appeared to his disciples after the third day from his death, alive again, according to the writings of the prophets, who foretold these and innumerable other miraculous events concerning him: from whom began the congregation of Christians, and has penetrated among all sort of men; nor does there remain any nation in the Roman world which continues strangers to his religion."
Then the author commented:
"If the Jews do not believe us, let them at least believed their own writers. Josephus, whom they esteem a very great man ... he spoke, in order to deliver historical truth, because he thought he was not lawful for him to deceive, while yet he was no believer, because of the hardness of his heart and his perfidious intention. However it was no prejudice to the truth that he was not a believer; but this adds more weight to his testimony, ..."
Before the TF quotation, our author said about Josephus:
"an author not to be rejected, when he writes against himself"

b) About 400: Hieronym. (Jerome) de Vir. Illustr. in Josepho.
Jerome's introduction of the Testimonium is as follows:
"Josephus in the eighteenth Book of Antiquities, most expressly acknowledges that Christ was slain by the Pharisees, on account of the greatness of his miracles; ...
[NOT in the TF! This is a speculation based on biased interpretations (and the gospels, especially John's)!]"
His TF (in Latin) shows noticeable differences with the one of Eusebius:
"At the same time there was Jesus, a wise man, if yet it be lawful to call him a man; for he was a doer of wonderful works, a teacher of those who willingly receive the truth. He had many followers, both of the Jews and of the Gentiles:-he was believed to be Christ. And then by the envy of our principal men ..."

c) About 410: Isidorus Pelusiota, the Scholar of Chrysostom, lib. iv. epist. 225
The TF is presented as follows:
"There was one Josephus, a Jew of the greatest reputation, and one that was zealous of the law; one also that paraphrased the Old Testament with truth, and acted valiantly for the Jews, and had shown that their settlement were nobler that can be described with words. Now since he made their interest give place to truth, for he would not support the opinion of impious men, I think it necessary to set down his words. What then does he say?"
Pelusiota's quote of the TF is very close to what is read today in 'Antiquities'.

B) Provide a badly needed piece of external evidence --by no one else that "the most famous of Hebrew historians, Flavius Josephus" (HC, I, 5)-- which is detailed and advantageous. Nothing of that sort was available then, not even something close to a tiny fraction of it (except of course the Abgar-Jesus letters and the Thaddaeus' story, all of them discovered by Eusebius!).

5.5. With the insertion of the Jesus' passage, the spurious story about James' death creating troubles for the Jews was not reproduced any more.
Why? Christians were not particularly fond of James (and his Jewishness); and according to the gospels, it is Jesus' execution, not James' one, that God avenged by having Jerusalem destroyed in 70 (Mk12:1-12, Mt21:33-46, Lk20:9-19, 1Th2:15-16).
Origen wrote:
"The same Josephus, ... when he was enquiring after the cause of the destruction of Jerusalem, and the demolition of the temple, and ought to have said that their machinations against Jesus were the cause of those miseries coming on the people, because they had slain that Christ, ... If, therefore, he says the desolation of Jerusalem befell the Jews for the sake of James, with how much greater reason might he have said that it happened for the sake of Jesus?" (Id. Contr. Cels.)
And later, Suidas (980) claimed to have read from an otherwise unknown (very likely spurious) work of Josephus:
"that the destruction of Jerusalem, and miseries of the Jews, were owing to their "putting Jesus to death"" (as already quoted in Section 3, C)

For a similar viewpoint (and with a well-polished scholarly outlook), read:
Testimonium Flavianum