Yes, the rumor is true. Mormons (a nickname for members of The Church of Jesus Christ of Latter-day Saints) don’t believe in the trinity. Some Christians believe that eliminates Mormons as Christians. Mormons, of course, think that qualifies them as Christians. Mormons believe only God can decide who is and is not a Christian and that for that reason, we must let people self-identify. Mormons accept as Christian anyone who says he is.
Mormons believe in God the Father, His Son, Jesus Christ, and in the Holy Ghost, as is stated in the first of thirteen official articles of faith. However, they believe these three are complete individuals, and that the oneness referred to in the Bible refers to unity, not physicality of some type. This is made clear in the New Testament:
21 That they all may be one; as thou, Father, art in me, and I in thee, that they also may be one in us: that the world may believe that thou hast sent me.
22 And the glory which thou gavest me I have given them; that they may be one, even as we are one:
23 I in them, and thou in me, that they may be made perfect in one; and that the world may know that thou hast sent me, and hast loved them, as thou hast loved me (John 17).
This is taken from the Great Intercessory Prayer. Jesus is asking God to make his followers one in the same way He and His followers are one. Is He asking that they be added to the Godhead? Of course not. He is merely asking that God help them to be unified by faith, love, and purpose. This demonstrates that it is this type of oneness the Bible refers to when it talks of God and Jesus as one. It is this same type of oneness we often refer to in marriage ceremonies, where couples are admonished to become as one—each uniquely individual, but unified completely in purpose and in love.
The word “trinity” is not in the Bible, nor is the formal definition of the trinity. This is an idea that developed out of Neo-Platonism and was put to a vote in various church councils held long after Jesus and His apostles were dead. It is a very post-biblical concept and was not formally accepted for several centuries. In Bible times, it was simply not taught at all. Instead, the Bible demonstrates in many ways the separateness of what Mormons (and the Bible) refer to as the Godhead. John teaches that Jesus never speaks His own thoughts, but merely tells us what God wants us to know:
13 Howbeit when he, the Spirit of truth, is come, he will guide you into all truth: for he shall not speak of himself; but whatsoever he shall hear, that shall he speak: and he will shew you things to come (John 16:13).
In Acts, we learn that Stephen had a vision in which he saw both God and Jesus Christ—individually, with Jesus on God’s right hand. (The fact that he saw God tells us something important about God. That is discussed in the article on God.) It should be noted he was murdered for reporting this vision to others, who didn’t want to know the information it taught.
55 But he, being full of the Holy Ghost, looked up stedfastly into heaven, and saw the glory of God, and Jesus standing on the right hand of God,
56 And said, Behold, I see the heavens opened, and the Son of man standing on the right hand of God. (Acts 7)
The proper Biblical name for God, Jesus Christ, and the Holy Ghost, when referred to as a unit, is Godhead. (See Acts 17:29 and Roman 1:20, as examples.) God is over all and is our literal Heavenly Father. He created our spirits, organizing them into a form that looked human, but lacked a physical body until we came to earth. Jesus Christ is His only begotten Son, and is the God of the Bible. It is He who speaks to mankind. God speaks to man only to introduce or testify of the Son, as happened at Jesus’ baptism. The Holy Ghost, unlike the other members of the Godhead, is a spirit. Jesus Christ and the Holy Ghost serve under God, carrying out His direction and purpose in love.
To learn more about each member of this Godhead, check out the Mormon Beliefs section of the website. Mormon beliefs about God are no secret!