Justice? Love? Intellect? These are the driving forces behind the creation of eternal torment for sundry crimes all finite in nature? Even in the Fourteenth century, it must have made little sense. To think that the earth sat as the center of the universe, attended by the orbiting sun and moon and planets, is understandable. To think that living beings were the handiwork of some master being, is understandable too, since they did not have the explanation of natural selection readily at hand. But the notion that the apogee of Divine Justice included such an unbalanced, disproportionate weighting of crime and punishment is impossible to grasp. So apologists are left only with the classic "Who Are You To Question God's Plan" defense. His ways are mysterious and not comprehensible to the little minds of men.
When I decided to have a go at rewriting Dante's vision of Hell, I planned to make one point clearly, loudly and often - that even within the context of the dream in which my story occurs, it isn't meant to be real. It's a simulation, an amusement park ride, a visit to the Holodeck. The 'souls' that suffer in my hell are no more sentient than animatronics. Yes, the illusion is that they suffer, and the emotional impact is the same, just as the emotional impact from a film isn't blunted by the fact that it isn't real. And yes, it is tempting to put the likes of a pedophile-priest or a terrorist into an everlasting torture chamber, but it isn't just. No matter how heinous their crimes, they were finite in scope. To prescribe an infinite punishment is to scoff at the concept of justice.
The details of hellish afterlives in Christianity and Islam, including their unlimited time scales, are what they are because they comprise the worst possible punishments anyone could dream up. Organized religion evolved under the pressure of many external forces, but certainly the notion of eternal damnation must have quickly gained in utility because it served as the ultimate consequence, the biggest possible stick to go with the biggest possible carrot. If you wish to dissuade people from a particular action, why bother threatening them with a finite consequence when you could offer up something far worse, since it cannot be verified or disputed? Just go all the way, peg the needle, turn the knob to eleven, and assure them that they'll be tormented forever. There isn't anything worse. No other religion is going to come along and one-up you with a more efficacious threat of damnation.
There is still a vertigo I feel when I contemplate that otherwise normal people here in the 21st century actually believe in Hell being literally true. I used to live in the Bible Belt, and had neighbors with signs in their yards about hellfire. I never spoke to them, as I tried to avoid them (just as I avoid a coworker here in Minnesota whose bumper sticker reads "Eternity: Smoking or Nonsmoking?") but I doubt these people would have found fault with the Irish Catholic vision of Hell that James Joyce relates in A Portrait Of The Artist As A Young Man:
"Ever to be in hell, never to be in heaven; ever to be shut off from the presence of God, never to enjoy the beatific vision; ever to be eaten with flames, gnawed by vermin, goaded with burning spikes, never to be free from those pains; ever to have the conscience upbraid one, the memory enrage, the mind filled with darkness and despair, never to escape; ever to curse and revile the foul demons who gloat fiendishly over the misery of their dupes, never to behold the shining raiment of the blessed spirits; ever to cry out of the abyss of fire to God for an instant, a single instant, of respite from such awful agony, never to receive, even for an instant, God's pardon; ever to suffer, never to enjoy; ever to be damned, never to be saved; ever, never; ever, never."
This is the product of Love? Justice? Intellect?