Eternity

I am currently reading the medieval narrative of Hell in Christianity and find the text quite dramatic though untenable. Everlasting souls, you see, are subjected to equally everlasting tortures in Hell. These souls are tormented in all possible ways and suffer from burns, lacerations, and other sequelae of atrocious demonic games. Still, there is one problem: if something lasts forever, then it cannot be changed, whereas something that can be injured is, alas, impermanent.