Eternal Torment Even for Christians?

I have been discussing the “universalistic” strand in parts of Christianity in the early centuries, which said that ultimately, everyone will be saved.  This was very much a minority opinion.  Most Christians continued to think that non-believers would be damned, forever, to some very nasty torments that would never end.

In fact, in many circles, more and more people came to be subject to the fires of eternity in the Christian imagination.  In the fourth and fifth centuries, with a massive in...