The Book of Enoch tells the story of how 200 rebel angels, or Watchers, decided to transgress the heavenly laws and ‘descend’ on to the plains and take wives from among mortal kind. The Watchers realize the implications of their transgressions, for they agree to swear an oath to the effect that their leader Shemyaza would take the blame if the whole ill-fated venture went terribly wrong.
One of their number, a leader named Azazel, is said to have "taught men to make swords. Other Watchers revealed to humans the knowledge of more scientific arts, such as astronomy. Far more disturbing is Kasdeja, who is said to have shown "the children of men all the wicked smitings of spirits and demons, and the smitings of the embryo in the womb, that it may pass away". In other words he taught women how to abort babies.
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