Concept
Fallen angels are angels who were expelled from heaven. The literal term "fallen angel" does not appear in any Abrahamic religious texts, but is used to describe angels cast out of heaven or angels who sinned. Such angels often tempt humans to sin. The idea of fallen angels derived from the Book of Enoch, a Jewish pseudepigraph, or the assumption that the "sons of God" () mentioned in Genesis 6:1–4 are angels. In the period immediately preceding the composition of the New Testament, some sects of Judaism, as well as many Christian Church Fathers, identified these same "sons of God" as fallen angels. During the late Second Temple period the biblical giants were sometimes considered the monstrous offspring of fallen angels and human women. In such accounts, God sends the Great Deluge to purge the world of these creatures; their bodies are destroyed, yet their peculiar souls survive, thereafter roaming the earth as demons. Rabbinic Judaism and Christian authorities after the third century rejected the Enochian writings and the notion of an illicit union between angels and women producing giants. Christian theology indicates the sins of fallen angels occur before the beginning of human history. Accordingly, fallen angels became identified with those led by Lucifer in rebellion against God, also equated with demons. Evidence for the belief in fallen angels among Muslims can be traced back to reports attributed to some of the companions of Muhammad, such as Ibn Abbas (619–687) and Abd Allah ibn Mas'ud (594–653). On the other hand, some Islamic scholars opposed the belief in fallen angels by stressing the piety of angels supported by verses of Quran, such as 16:49 and 66:6, although none of these verses declare angels as immune from sin. One of the first opponents of the concept of fallen angels was the early and influential Islamic ascetic Hasan of Basra (642–728). To support the doctrine of infallible angels, he pointed at verses which stressed the piety of angels, while simultaneously reinterpreting verses which might imply acknowledgement of fallen angels.
