The Basics of Judaism: G-d & Torah: Fallen Angels:
Who were the fallen angels? Was Satan one of them?
In the Jewish tradition, Satan isn't a "fallen" angel;
he's an angel whose occupation is tempting men to sin,
as illustrated in Ch.1 of Job. "Satan" means something
like "adversary"; it's used in that generic sense in
Num.22:22. Satan's proper name is Samael. He guided
the serpent in the Garden of Eden to tempt Eve. The
angels who fell in Enoch's time were tempted by human
women, as told in Gen.6:1-4. Their leaders were Uza
(or Shemchazai) and Azael; the names Uza and Azael
may be related to the Azazel of Lev.Ch.16.
The Midrash (end of Devarim Rabbah) says that Uza and Azael were punished by being suspended between heaven and earth.
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