Whereas many theologically conservative evangelical Christians, and most if not all fundamentalist Christians, believe both in a literal hell and that at least some poor souls are suffering there for all eternity, there are plenty of others — Christians and non-Christians alike — who strongly disagree.
Among Christians who disagree about the reality of hell are some theological liberals, progressives, and moderates who do not take the Bible to be absolutely infallible, and who do not read it in strictly literalistic terms. Many have familiarized themselves with the fruits of contemporary secular biblical scholarship (including, for instance, the work of many popular historical Jesus scholars), which has certainly challenged older, more traditional assumptions about the very nature and meaning of the Bible.
Then, of course, there are the Universalists. As a theological position, Christian Universalism maintains that salvation is literally “universal” in application and scope; Universalists hold that an all-loving and all-powerful God simply would never condemn anyone to eternal damnation. Universalism even existed as a formal Christian denomination in the U.S. until 1961, when it merged with Unitarianism (a Christian denomination so named for its non-belief in the theological concept of the Trinity) to form today’s Unitarian Universalist Association (UUA), a “post-Christian” religious organization headquartered in Boston.
We are also seeing a handful of contemporary evangelical thinkers and writers who have begun openly speculating about the possibility that salvation just might be universal, after all. For example, popular pastor/author Rob Bell recently created a stir in evangelical circles with his book Love Wins: A Book About Heaven, Hell, and the Fate of Every Person Who Ever Lived, in which he frankly raises such sensitive questions, and seems at least somewhat open to considering such “unorthodox” alternative views as viable possibilities.
Moving from the Protestant wing of Christianity over to its Catholic branch, we find that eternal heaven and eternal hell are not the only two possibilities regarding afterlife destinations. Catholics also traditionally believe in purgatory, a place of temporary post-mortem existence for souls who are not quite ready for heaven, but also not doomed outright to hell. Purgatory is thus seen as a place where additional purification is undergone, until the soul is sufficiently purged of sin to be able at last to enter heaven.
Moving beyond the Christian tradition altogether, we find that Judaism has some distinctive views of its own regarding the afterlife. Of course, Jewish beliefs can be pretty diverse, too, and not all Jews are of one mind on the matter. Some Jews are largely unconcerned with it, preferring to keep their focus upon the here and now, rather than upon the hereafter; the afterlife, in their view, will take care of itself. Other Jews may adopt the traditional rabbinic view that the righteous of all nations (not just righteous Jews, mind you) will go to paradise — and while the wicked may go to hell for punishment, no one stays in hell for longer than twelve months. In this view, the Jewish hell functions more or less like the Catholic purgatory, and eternal life in the World to Come is an eventuality open to virtually everyone (with the possible exception of only the most stubbornly unrepentant, and hence the irredeemably truly wicked).
Once we proceed beyond the Judeo-Christian tradition, we find even more diversity regarding religious and spiritual views regarding the afterlife. In contrast to the usual traditional Western belief that everybody gets just one life on this Earth, and hence only one chance to “get it right,” traditional Eastern religions such as Hinduism and Buddhism instead maintain that everyone actually lives numerous lifetimes on this Earth, reincarnating over and over — as often as necessary, affording themselves of as many such “chances” as may be needed — before eventually “getting it right.”
“Getting it right” for Christianity means attaining salvation from sin, whereas “getting it right” for Hindus and Buddhists means overcoming the karma that perpetuates their otherwise endless reincarnations here on Earth (and/or elsewhere, as well), thereby attaining final liberation from the repetitive cycle of birth, death, and rebirth. For Hindus, this is generally understood to be achieved by attaining union or communion with God, whereas for Buddhists such eternal release is generally couched in the non-theistic terms of attaining the infinite bliss of nirvana; but in each case, the end result is one which ultimately everyone will eventually attain — even if it takes literally millions of reincarnations, and millions of lifetimes, to finally “get there.”
So, the possibility of universal salvation for all — or of universal “liberation,” to put it in Eastern metaphysical terms — is far from unknown, or unheard of, within the broader global religious context.