The Mormon Church’s real name is the Church of Jesus Christ of Latter-day Saints. Its original name was the Church of Christ. This indicates the Church as a Christian one, at least by name – and Mormons would testify that they are Christians in practice, too. But many Christians claim that Mormons are not Christian at all. Why is this?
Mormons have many differing beliefs from Catholics or Protestant Christian beliefs. Indeed, Mormons believe many things that no one else seems to believe. As Mormons believe that their church is the one true church, they are not surprised that no one shares all of their beliefs. But these different beliefs are different enough to surprise many Christians into strong disagreement.
Joseph Smith, the founder of the Mormon Church, has always drawn fire and drawn doubt. Many Christians even believe that Mormons worship their founder, confusing respect with cultism. Joseph Smith acted as the first Mormon prophet in this, the “last dispensation of time,” and received many revelations on the organization, doctrines, and purpose of the Mormon Church. He translated the Book of Mormon, a record of the doings and teachings of an ancient people and their prophets, on the American continents. Through him, God reintroduced His temples and priesthood authority into the world, restoring the ancient true church of Christ.
Most Christians believe that the Bible is the only scripture God has given to us. The Book of Mormon (and the Doctrine and Covenants and the Pearl of Great Price) is additional scripture. And even though the Book of Mormon is another testament of Jesus Christ, because it adds another witness of Him to the Bible, many do not see it as a Christian book.
Mormons also believe, again, in prophets and continuing revelation. They believe that God speaks to their prophets and directs their Church. In a way, then, they are always adding to the Bible. For further discussion on this, go to our page about Luke 16:16.
Mormon temples also strike many Christians as very strange. These temples are not Mormon church buildings, but something more sacred and holy. Inside the Mormon temple, Mormons perform ordinances that most Christians are not familiar with. Ordinances such as baptisms for the dead, the endowment, and eternal marriage are unique to Mormonism. You may want to read our pages about temple ordinances and eternal marriage. Mormons see these as essential for salvation and exaltation.
Exaltation is another point where Mormons differ from many Christians. Mormons believe that, through the gospel of Jesus Christ and the plan of salvation, men and women can become like God, which doctrine was commonly accepted in the ancient church. Which is not to say that we ever stop worshipping God or become greater than Him, but that, as His spirit children, He wants us to progress eternally, not reach a certain point and learn no more. Jesus Christ is our Redeemer and a perfect example for us to follow. He has promised us that if we inherit His kingdom, we will be heirs to all He has. This is not blasphemy, nor is it arrogant. It is revealing of Christ’s doctrine, His generousity to those who become exalted.
Mormons do not share the doctrine of the Trinity as being three bodiless (incorporeal) gods in one. Mormons do not believe in the Trinity, or accept the Nicene Creed, but believe that God, Jesus Christ, and the Holy Ghost are three separate and distinct beings, united in purpose. God the Father and Jesus Christ have perfect, glorious, resurrected bodies of flesh and bone, else why was Christ resurrected at all? Although the doctrine of the Trinity was decided centuries after Jesus Christ, some Christians believe that Mormon rejection of the doctrine leaves them out of Christianity.
In the end, however, as Mormons believe in the divinity of Jesus Christ and salvation through him, as they worship Him, God, and the Holy Ghost (not Joseph Smith or anyone else), they are difficult not to define as Christian in the basic sense. Christ leads and directs Mormon prophets through revelation. If Mormons are not Christian, the question must be “what is Christianity, then?”
Mormons do not believe that they can earn their way into heaven through their works. They believe that they can be saved by grace. However, they do believe in the admonitions of James, that faith without works is dead. Faith is an action word, and it is manifest on our intentions, beliefs, and behavior. We believe in a God who gives commandments. The works we refer to are two-fold: First, repentance, and second, keeping the commandments of God. If you take away all the text in the Bible that refers to works and commandments, the holy book would be very small indeed.
An addition to my reply. Those Christians who believe that belief is enough to save us tend to ignore the many passages of biblical scripture that speak of works. The Book of James is notable. Mormons do not lie about their belief that works are valuable, but we cannot be saved by our own efforts alone, and that is Mormon doctrine.