Jude 1:7 New International Version
In a similar way, Sodom and Gomorrah and the surrounding towns gave themselves up to sexual immorality and perversion. They serve as an example of those who suffer the punishment of eternal fire.
People of Sodom and Gomorrah will be burned in eternal fire.
If anyone will not welcome you or listen to your words, leave that home or town and shake the dust off your feet. 15 Truly I tell you, it will be more bearable for Sodom and Gomorrah on the day of judgment than for that town.
Isn't eternal fire the ultimate punishment? How can that town be punished even more severely?