Like most other religions, the Church of Jesus Christ of Latter-day Saints makes a not-so-unique claim to uniqueness--the only religion that provides the true path back to God. In doing so, however, hopefully the LDS Church can rise above the intolerance practiced by other religions who make such claims.
If a certain Church is the only true church, will those people who know about it but don't join it burn in hell? Absolutely not. But members of many faiths, perhaps including some Bible-bashing Mormons, seem to think (and almost revel in the belief) that anyone who does not belong to their religion will suffer some sort of hell fire.
Where does such intolerance come from? Some LDS scriptures, incorrectly interpreted, can give Latter-day Saints the wrong impression that individuals only get one chance to accept the true gospel. For example, Alma chapter 34 in the Book of Mormon states that
I beseech of you that ye do not procrastinate the day of your repentance until the end; for after this day of life, which is given us to prepare for eternity, behold, if we do not improve our time while in this life, then cometh the night of darkness wherein there can be no labor performed.This verse of scripture says nothing about joining the only true church, mind you, but it's tempting to think that it does. The only requirement stated at all in the verse from Alma is that we improve our time (or become better people) while in this life. Most people--of any religion, or no religion at all--do a rather good job at that.
The real temptation to not tolerate other faiths comes from fear. The Nazis had this fear. The Communists had it with gusto. And so do many religions. Such fear comes from a deep-seated realization that what one believes is actually not the truth. Based on that fact alone, Latter-day Saints, of all people, should be the most tolerant of other religions.
A variety of falsehoods have leaked their way into Mormonism since the earliest forms of apostate Christianity. The most unfortunate of these untruths is intolerance, manifested most commonly by the belief that those who disagree with us are somehow not as good as us.
Joseph Smith explained his abhorrence of such 'religious fervor' during his boyhood years:
...there was in the place where we lived an unusual excitement on the subject of religion. It...soon became general among all the sects in that region of country. ...great multitudes united themselves to the different religious parties, which created no small stir and division amongst the people, some crying, “Lo, here!” and others, “Lo, there!”But it didn't start there. Such intolerance, if it didn't start sooner, made its debut in conjunction with the kicking of apostate Christendom into high gear.
For, notwithstanding the great love which the converts to these different faiths expressed at the time of their conversion, and the great zeal manifested by the respective clergy, who were active in getting up and promoting this extraordinary scene of religious feeling...when the converts began to file off, some to one party and some to another, it was seen that the seemingly good feelings of both the priests and the converts were more pretended than real; for a scene of great confusion and bad feeling ensued—priest contending against priest, and convert against convert; so that all their good feelings one for another, if they ever had any, were entirely lost in a strife of words and a contest about opinions.
After being recognized as the official religion of the Roman empire, Christianity quickly came to evince much less tolerance for other faiths than Rome's pagan religions had done. Christians, now in the ascendancy, brooked very little disagreement with their religion. Their most vile hatred was reserved for the Jews, whom Christians took to calling "the murderers of Christ". Prefiguring Adolf Hitler and other monsters in the flesh, Christians of the third century (and afterward) constantly fostered hatred for everything Jewish. Reasoning quite irrationally that, because all Jews were guilty of being Christ killers, Christians styled themselves as the new Israel. Using this flimsy justification, the Christians occupied the Holy Land, taking down the unbelievers in great swathes.
Over the intervening centuries, Christians, Muslims, and Jews have attempted to perfect their various arts of intolerance, ironically all in the name of God, the most tolerant of all.
Intolerance of other religions is a distinctively apostate activity, born of a subliminal fear that one no longer has the truth. This not being a good reason for intolerance, we can discover no reason at all for the adherents of any faith to show a lack of tolerance for the members of any other. Hundreds of thousands of Latter-day Saints stand before their congregations on Sunday and state that they "know that the Church is true". I can think of no better basis than this for complete tolerance of the beliefs of others.
Is it important for everyone who wants to make the most of their eternities to accept God's true church? Sure. I think so. Eventually. But we shouldn't promulgate the decidedly non-doctrinal claims that non-believers are less of persons than we are, or that someone will burn in the fires of hell if they don't join our church.
God loves all of His children. He has tolerance for them. So should we. For members of the Church of Jesus Christ of Latter-day Saints, one of the best manifestations that we really "know the Church is true" is to follow the example of our Father in Heaven by celebrating the choice of others to belong to a church or religion different than our own.