Jude 1:5-7

Three examples are given as revealing the doom of such evil-livers: the faithless Israelites in the wilderness, who were destroyed; the fallen angels, who are kept in bonds under darkness until the Judgment Day; and the Cities of the Plain, which suffered the punishment of eternal fire.

Jude 1:6. The sin of the angels was twofold: (a) they kept not their own principality, the sphere allotted to them by God (Deuteronomy 32:8, Enoch 18:13, 21:3) the sin of pride or disobedience; (b) they left their proper habitation, they came down to earth (Genesis 6:1 *; Enoch, passim) the sin of lust; the fall of the angels through lust is one of the main subjects in Enoch. The tradition as to their punishment is derived from Enoch (cf. 10:4, 12, 54:3). (For the use of Enoch by Jude, see the parallels quoted by Chase.) The whole passage should be compared with 2 Peter 2:1, which is based on it.