5 So I want to remind you, though you already know these things, that Jesus first rescued the nation of Israel from Egypt, but later he destroyed those who did not remain faithful. 6 And I remind you of the angels who did not stay within the limits of authority God gave them but left the place where they belonged. God has kept them securely chained in prisons of darkness, waiting for the great day of judgment. 7 And don't forget Sodom and Gomorrah and their neighboring towns, which were filled with immorality and every kind of sexual perversion. Those cities were destroyed by fire and serve as a warning of the eternal fire of God's judgment.

Matthew Henry's Commentary on Jude 1:5-7

Commentary on Jude 1:5-7

(Read Jude 1:5-7)

Outward privileges, profession, and apparent conversion, could not secure those from the vengeance of God, who turned aside in unbelief and disobedience. The destruction of the unbelieving Israelites in the wilderness, shows that none ought to presume on their privileges. They had miracles as their daily bread; yet even they perished in unbelief. A great number of the angels were not pleased with the stations God allotted to them; pride was the main and direct cause or occasion of their fall. The fallen angels are kept to the judgment of the great day; and shall fallen men escape it? Surely not. Consider this in due time. The destruction of Sodom is a loud warning to all, to take heed of, and flee from fleshly lusts that war against the soul, Job 15:16.