We Unitarians, one of whom I have had the Honour to be, for more than sixty Years, do not indulge our Malignity in profane Cursing and Swearing, against you Calvinists; one of whom I know not how long you have been. You and I, once saw Calvin and Arius, on the Plafond of the Cathedral of St. John the Second in Spain roasting in the Flames of Hell. We Unitarians do not delight in thinking that Plato and Cicero, Tacitus Quintilian Plyny and even Diderot, are sweltering under the scalding drops of divine Vengeance, for all Eternity.
-- John Adams to John Quincy Adams, March 28, 1816, Ibid, reel 430.
I've written before on my disbelief in the possibility of the eternal damnation as taught by some traditional orthodox Christians. If fundamentalists are right John Adams (and Jefferson, Franklin, and probably Washington, Madison, G. Morris and other key American Founders) is roasting in the Flames of Hell as we speak (or at least will be, according to some understandings of the Bible, indeed what the Book of Revelation actually teaches, the dead are currently neither in Heaven nor Hell, but will be after the final judgment).
This link from an atheist website well explores the topic. If God is just, no one goes to Hell for eternity, because Hell = infinite punishment for finite sins. It's like saying 2+2 = 5 and you have to believe it because an infallible God says it. Not one human being deserves this. I will concede that some concepts of Hell could be just. For instance 1) temporary punishment like purgatory, 2) a place where human beings go by choice because they don't want to be in God's presence, keeping in mind that no one would choose eternal torture, therefore Hell must be a place where humans get to enjoy sinning for all of eternity not in God's presence, or 3) annihilation, which is what atheists think they are going to get anyway.
But Jonathan Edwards' traditional understanding of Hell as eternal torture not only is morally indefensible, but also, I would argue, risks corrupting the soul and turning human beings into vicious, mean spiritual creatures more likely to do great evil. Militant Islam likewise believes in a wrathful Allah who will burn infidels in a torturous Hell for all of eternity and we see what the fruits of that religion are.
"But as for those who disbelieve, garments of fire will be cut out for them; boiling fluid will be poured down on their heads, whereby that which is in their bellies, and their skins too, will be melted; and for them are hooked rods of iron. Whenever, in their anguish, they would go forth from thence they are driven back therein and (it is said unto them): Taste the doom of burning."
--The Qur'an, sura 22:19-22
"Those who disbelieve Our revelations, We shall expose them to the Fire. As often as their skins are consumed We shall exchange them for fresh skins that they may taste the torment."
--The Qur'an, sura 4:56
Consider Fred Phelps. I know most evangelicals/fundamentalists don't agree with his positions, but after studying his theology in meticulous detail, I can attest that every single position he takes has a sound scriptural basis and is defensible on traditional orthodox Christian grounds; indeed Phelps is a 5-point Calvinist. It's just that there is more than one way to skin a cat and to "literally" interpret the Bible. And Phelps simply opts for the most mean spirited, uncharitable, and unkind interpretation of Scripture, almost like the opposite side of the coin of Richard Dawkins. (Phelps' understanding of the Biblical God is what Dawkins makes the Biblical God out to be.)
Conservative evangelicals can and should disagree with Phelps' mean spirited approach to the Bible. But they are being utterly disingenuous if they argue Phelps really isn't preaching from the Bible as they do. No, he is; he just constructs different interpretations or doctrines out of a literal reading of scripture. The notion that God loves the sinner but hates the sin is simply doctrine gleaned from the Bible; indeed, the notion that God hates people, likewise has just as sound a scriptural basis. The Phelps family would ask: Who is Easu? What does God think of workers of Iniquity? The Bible says he hated Easu and God hates workers of Iniquity. Hence God hates people.
And Phelps' view on Hell is exactly in line with the traditional Edwardsian view of Hell as eternal torture.
Phelps is a self-evident example of a corrupted soul. The Westboro Baptist Church and Bid Ladenesq. militant Islam are, at worst, examples of what belief in the Edwardsian view of Hell can do to the human soul. Avoid it if you can. I would imagine that a just God will punish for beliefs such as this (temporarily of course) for giving Him a bad name.