Christianity consists of a set of beliefs of widely differing age and origins. First comes GOD, creator of heaven and earth, invisible and all-powerful, creating out of nothing and enjoying mankind to obey his laws. This is the god of the Jews as seen in the Old Testament, as a Creator in Genesis, and as a Lawgiver in Exodus.

Next comes the person of Joshua ben Joseph, the carpenter’s son from Nazareth , aka Jesus, the ‘anointed one’ (in Greek christos), whom some Jews regarded as the saviour announced by the prophets, while others did not. Jesus was in line with a new movement that gave the Scriptures a more generous interpretation (the Sabbath is made for man, not man for the Sabbath) .As a Jew, Jesus would not have regarded himself as any more than a teacher, albeit an inspired one. However, his doctrine was addressed to all men, not only to Jews, and his followers came to regard him as the incarnate son of God, immaculately conceived and born of a human mother, Mary. The story of his ministry is told in the four Gospels, Greek documents from the late 1st to mid-2nd centuries AD. Through the mediation of Jesus, fallen mankind can achieve everlasting life after death, by repentance and belief in the Master.

During the Next four centuries there gradually evolved the basic framework of Christian theology, which tries to give some kind of rational account, insofar as this is possible, of Christian doctrine, using Greek metaphysics as a basis, in particular neo-Platonic, Aristotelian and stoic speculations. Thus arose an orthodox line of Christian belief, all deviations being branded as heresies.

One difficulty was to explain the relation of God the father to God the Son. E.g. some denied that the Son ever was truly human (Docetism), while others denied that he was always divine, because he must have been created by the father (Arianism). The orthodox dogma finally decreed at the Council of Nicaea (325) that Father and Son were of the same substance (omoousioi), not as Arius had said of similar substance (omoiousioi). A further doctrine that was gradually elaborated was that of the Holy Trinity: God as father, Son and Holy Spirit, three aspects of one God.

The set of Christian dogmata as a whole is a somewhat varied lot that do not all go comfortably together. In theory, an adherent is supposed to declare his belief in them. In practise, it is not easy either to check this, or make out what it amounts to. However, neither of these things is necessary for the religion to have inspired many generations of men to implement their beliefs to the best of their limited powers.