Mormons believe in three separate gods for the Trinity, not one God in three persons, for starters. That being said, they deny Christ as God and their baptisms are invalid. That is why they are not considered Christian.
For what it’s worth, here is a fairly precise explanation of the difference between the Mormon and mainstream Christian doctrines of the Trinity, from my Mormon point of view. There are several issues that need to be considered.
What is God?
Mainstream Christianity teaches that God is an indivisible, “simple” (i.e., “without parts” or completely homogeneous), eternally unchanging spiritual essence. This doctrine was adopted by Christians in the second century from the Greek philosophy current at the time. For example, here is a quotation from the pagan Middle Platonist philosopher, Numenius.
But let no one laugh, if I affirm that the name of the incorporeal is “essence” and “being.” And the cause of the name “being” is that it has not been generated nor will be destroyed, nor is it subject to any other motion at all, nor any change for better or for worse; but is simple and unchangeable, and in the same idea, and neither willingly departs from its sameness, nor is compelled by any other to depart. (Numenius, quoted by Eusebius, Preparation for the Gospel 11:10 )
Compare Numenius’s description with that of Irenaeus, a Christian writer of the late second century, who had adopted the philosophical view of God.
For the Father of all is at a vast distance from those affections and passions which operate among men. He is a simple, uncompounded Being, without diverse members, and altogether like, and equal to himself, since He is wholly understanding, and wholly spirit, and wholly thought, and wholly intelligence, and wholly reason, and wholly hearing, and wholly seeing, and wholly light, and the whole source of all that is good–even as the religious and pious are wont to speak concerning God. (Irenaeus, Against Heresies 2:13:3, in ANF 1:374.)
Tertullian, a Christian who wrote at the turn of the third century, explicitly stated that his idea of the Father was essentially that of the philosophers.
Whatever attributes therefore you require as worthy of God, must be found in the Father, who is invisible and unapproachable, and placid, and (so to speak) the God of the philosophers; whereas those qualities which you censure as unworthy must be supposed to be in the Son . . . . (Tertullian, Against Marcion 2:27, in ANF 3:319.)
Paul had warned the earliest Christians not to be deceived by philosophy. “Beware lest any man spoil you through philosophy and vain deceit, after the tradition of men, after the rudiments of the world, and not after Christ” (Colossians 2:8). Certainly earliest Christianity and Greek philosophy had some things in common. Was this one of them, or was it one of those things that Paul warned against?
Mormons believe that this was an alteration of original Christian teachings, because we believe that God is “anthropomorphic,” in that he has a body in human form. This contention is abundantly supported by modern historical scholarship. For example, Christopher Stead, a professor at the Cambridge Divinity School, wrote an excellent book on how Greek philosophy was incorporated into Christian teaching. He wrote this about how the Biblical authors pictured God.
“The Hebrews . . . pictured the God whom they worshipped as having a body and mind like our own, though transcending humanity in the splendour of his appearance, in his power, his wisdom, and the constancy of his care for his creatures.” (Christopher Stead, Philosophy in Christian Antiquity, Cambridge: Cambridge University Press, 1996, 120.)
A clear example is found in the early Jewish Christian writing, the
Clementine Homilies.
And Simon said: “I should like to know, Peter, if you really believe that the shape of man has been moulded after the shape of God.” And Peter said: “I am really quite certain, Simon, that this is the case . . . . It is the shape of the just God.” (Clementine Homilies 16:19, in ANF 8:316.)
Origen, a third-century Christian writer, said that while he and many other Christians accepted a philosophical view of God, the Jews and some Christians viewed God as anthropomorphic. He said this was not a settled teaching within Christianity at that time.
“The Jews indeed, but also some of our people, supposed that God should be understood as a man, that is, adorned with human members and human appearance. But the philosophers despise these stories as fabulous and formed in the likeness of poetic fictions.” (Origen, Homilies on Genesis 3:1)
We shall inquire, however, whether the thing which Greek philosophers call asomaton, or “incorporeal,” is found in holy Scripture under another name. For it is also to be a subject of investigation how God himself is to be understood,–whether as corporeal, and formed according to some shape, or of a different nature from bodies,–a point which is not clearly indicated in our teaching. (Origen, De Principiis Preface 9, in ANF 4:241.)
Mainstream Christians might object that the Bible says that “God is Spirit” (John 4:24). But what does that mean? John also said that “God is light” (1 John 1:5), and “God is love” (1 John 4:8). Paul said that “he that is joined unto the Lord is one spirit” (1 Corinthians 6:17), although men obviously have both spirits and bodies. Why do mainstream Christians automatically assume that “God is Spirit” means that God has no body? Anglican historian and Bishop of London, J.W.C. Wand, explained, “It is easy to see what influence this school of thought * must have had upon Christian leaders. It was from it that they learnt what was involved in a metaphysical sense by calling God a Spirit.” (J.W.C Wand, A History of the Early Church to A.D. 500, New York, Routledge, 1994, 140.) You guessed it—Christians got this idea from the Greek philosophers. On the other hand, Christopher Stead writes that the Hebrews would have given a completely different interpretation to John 4:24.
By saying that God is spiritual, we do not mean that he has no body . . . but rather that he is the source of a mysterious life-giving power and energy that animates the human body, and himself possesses this energy in the fullest measure. (Stead, Philosophy in Christian Antiquity, 98.)
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Continued in next post…**
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