The web site Mastemajewishgod.doc summarizes portrayals of Mastema, which demonstrate the contentions of Baruch, the late Jewish vegetarian prophets, Origen, and Tertullian that the Jews did in fact worship demons when they sacrificed animals.  Mastema is described in "The Book of Jubilees" as well as in "Fragments of a Zadokite Work."  Part of the following on Mastema is my periphasing and commenting on the material in the above site.

"When Mastema, the leader of the spirits, came, he said: 'Lord creator, leave some of them before me; let them listen to me and do everything that I tell them, because if none of them is left for me I shall not be able to exercise the authority of my will among mankind. For they are meant for (the purposes of) destroying and misleading before my punishment because the evil of mankind is great.' Then he said that a tenth of them should be left before him, while he would make nine parts descend to the place of judgment." - Jubilees 10:8-9

    The name Mastema is thought to have been derived from the Hebrew, Mastim, a participle of Satam, meaning 'one who is adverse' or 'inimical.' This definition is much like the the definition of Satan as the adversary.  The word is sometimes used in the plural to show there was a Mastema class as well as a prince Mastema, a system which is also parallel to the the system among demons described in 1 Enoch 40:7).
 
 

"And they made for themselves molten images, and they worshipped each the idol, the molten image which they had made for themselves, and they began to make graven images and unclean simulacra, and malignant spirits assisted and seduced (them) into committing transgression and uncleanness. And the prince Mastema exerted himself to do all this, and he sent forth other spirits, those which were put under his hand, to do all manner of wrong and sin, and all manner of transgression, to corrupt and destroy and to shed blood upon the earth. Jubilees 11:4-6
 
 

"Then Prince Mastema came and said before God: 'Abraham does indeed love his son Isaac and finds him more pleasing than anyone else. Tell him to offer him as a sacrifice on an altar. Than you will see whether he performs this order and will know whether he is faithful in everything through which you test him.'" - "Jubilees" 17:16
 
 

"You know who spoke to you at Mt. Sinai and what the prince of Mastema wanted to do to you while you were returning to Egypt - on the way at the shady fir tree. Did he not wish with all his strength to kill you and to save the Egyptians from your power because he saw that you were sent to carry out punishment and revenge on the Egyptians?" - "Jubilees" 48:2-3

    These scriptures expose the demonic origins of orthodox Judaism, and in fact the origins of all orthodoxies which support the governments of the world, and  have been likened to the scriptures in 1 Chronicles 21:1 and 2 Samuel 24:1 in which it is Satan and not God who asks David to take a census.  The omniscient God of all life does not need to take a census, but governments of this world, which are all initiated by Satan, desiring to control their populations, do.
 
 

"And the prince Mastema stood up against thee, and sought to cast thee into the hands of Pharaoh, and he helped the Egyptian sorcerers, and they stood up and wrought before thee the evils indeed we permitted them to work, but the remedies we did not allow to be wrought by their hands." - Jubilees 48:9-10

"And notwithstanding all (these) signs and wonders the prince Mastema was not put to shame because he took courage and cried to the Egyptians to pursue after thee with all the powers of the Egyptians, with their chariots, and with their horses, and with all the hosts of the peoples of Egypt." - Jubilees 48:12
 
 

     It is the demon Mastema who slays the first-born in the land of Egypt, though this is attributed to the Lord in Exodus 12:29.

"For on this night -the beginning of the festival and the beginning of the joy- ye were eating the passover in Egypt, when all the powers of Mastema had been let loose to slay all the first-born in the land of Egypt, from the first-born of Pharaoh to the first-born of the captive maid-servant in the mill, and to the cattle." - Jubilees 49:2
 

     "...the whole assembly of the congregation of Israel shall kill their lambs in the evening.  Then they shall take some of the blood and put it on the two doorposts and the lintel of the houses in which they eat them. They shall eat the flesh that night."  Exodus 12: 6-8.

     "Then Moses called all the elders of Israel and said to them `Select lambs for yourselves according to your families, and kill the passover lamb. Take a bunch of hyssop and dip it in the blood which is in the basin and touch the lintel and the two doorposts with the blood which is in the basin.'"  Exodus 12: 21-22.

     This orthodox portrayal of Moses was a lie taught by animal-sacrificing cattlemen for profit.  It is a fabrication that contradicted  the vegetarian covenant for all creatures commanded by Deity in the first chapter of Genesis in verses 29 and 30.

This false Moses contradicts the prophecies of peace for all creatures.

  And Here the Moses constructed by the cattleman cult that became orthodox Judaism promotes carnivorism as an eternal practice, thus contradicting all the prophecies of peace for all creation by Jewish, Hindu, Tibetan, Hopi and Mayan seers and prophets.

  "You shall observe this rite as an ordinance for you and your sons forever."  Genesis 12: 24.

 Cruelty is inherent in all sacrifice. A deity of infinite love is cast aside by the orthodox Moses constructed by cattleman in favor of a entity--history calls these entities demons--desiring blood and sacrifice.

    Sacrificing the first-born:

"All the firstlings of your cattle that are males shall be the Lord's.  Every firstling of an ass you shall redeem with a lamb, or if you will not redeem it, you shall break its neck." Exodus 13: 12-13.

 The late Jewish prophets regarded this Moses as a lie taught by false prophets.  So too Jesus, James, Peter and John the Baptist as presented in the Ebionite Gospel by Epiphanius regarded the Pentateuch as false scriptures written by men.  See Epiphanius' discussion in the Panarion.
 
 

     I wish here to quote Barry Goldwater, not because I share his politics, or the politics of any established party, for the spiritual person realizes that there is no authority but God, and that all worldly authorities are Mammon, or Money, but because he did have a keen sense of truth when he said: "Extremism in the cause of virtue is no vice; and extremism in the cause of vice is no virtue."  Industrial civilization as we know it is in fact extremism in the cause of vice, in that industries' toxins have polluted the very air we breathe and water we dream, and even much of the earth we walk upon.  The pejorative connotations of the word "extremism" have the connotation of going overboard, of going too far, of being excessive.  In the spiritual life, one cannot be excessive in extending compassion to the creatures of the earth, and to creation.  As great as one's compassion may be, it is limited compared to the infinite love and all-compassionate nature of Deity, as seen by Hindus and Buddhists or the true remnant who may be of any faith.  The Jains see the Forces of Creation as a Divine Order, rather than as specific divine personalities.

   So the reader of "Jubilees" and the Ethiopic Book of Enoch sees that the demonic origins of what is now regarded as orthodox Judaism was more obvious in times past, and we see also why the orthodox do not encourage studying opposition views and non-orthodox scriptures, such as "Jubilees" and the Ethiopic Book of Enoch. This scriptures make it plain that there was a strong tradition asserting that bloodshed of any kind was evil, and that this definitely included the sacrificing of animals.  Moreover, the renunciate life was seen as ideal in that it did not interfere with nature.  The life of the householder, who married and raised crops and perhaps animals for their milk, was not regarded as as high a calling as the renunciate life. Consult the Jain Sutras, the Laws of Manu, and the Institutes of Vishnu.  The Jewish Rechabites and the Arab Nabateans were two groups that would not even cultivate the ground, because of the "unrighteous tilling" of the soil. The Book of Enoch makes it clear that even those who plant crops are to till the soil righteously, which means that they were involved in types of agriculture that we would call top of the ground mulching or non-invasive permaculture, so as not to disturb the animal and plant life that already exist. The Nabateans, one may conjecture, could have received their teachings from Moses on Mt. Nebo. For the word manna in ancient Hebrew was simply the Sanskrit word manas, which meant spiritual knowledge.  The forty years in the Sinai wilderness was in fact a time of immense spiritual purity in that the entire community of Israelites, who wore the Hindu bindi, were in conformity with the vegetarian covenant of Genesis. Naba is the root of words meaning both fruit and prophecy, and to the original Jewish renunciate, as well as to the Jain and Brahman renunciates, the two were related.  The fruit eaters, those who ate from the trees and bushes of nature, were spared even the karma of growing vegetables from soil where insects and other animals were displaced, killed or abused. Those who have lived in the wilderness for periods of time, eating only what is there, and drinking from natural sources, at the same time meditating and praying to be a pure channel, know that these acts of "extreme purity" cause an inner transformation and enlightenment. It is in fact a formula for transformation that has always worked as long as my intentions were pure.