Jude 1:5-7

5Now I want to remind you, although you once fully knew it, that Jesus, who saved a people out of the land of Egypt, afterward destroyed those who did not believe. 6And the angels who did not stay within their own position of authority, but left their proper dwelling, he has kept in eternal chains under gloomy darkness until the judgment of the great day— 7just as Sodom and Gomorrah and the surrounding cities, which likewise indulged in sexual immorality and pursued unnatural desire, serve as an example by undergoing a punishment of eternal fire.