“Even as Sodom and Gomorrha, and the cities about them in like manner, giving themselves over to fornication, and going after strange flesh, are set forth for an example, suffering the vengeance of eternal fire.”
King James Version (KJV)
1:7 The cities which gave themselves over to fornication - The word here means, unnatural lusts. Are set forth as an example, suffering the vengeance of eternal fire - That is, the vengeance which they suffered is an example or a type of eternal fire.
Jude 1:7 Even as Sodom and Gomorrha. See notes on 2Pe 2:6,10. For their lasciviousness terrible destruction came upon them. Are set forth for an example. Utterly destroyed by fire they are an example that points to the eternal fire.