A speech by LDS apostle Bruce R. McConkie shows how Mormonism has for years misrepresented what the Christian world teaches and believes about the Trinity. Here is an excerpt from a speech he gave at BYU:
True and saving worship is found only among those who know the truth about God and the Godhead and who understand the true relationship men should have with each member of that Eternal Presidency.
It follows that the devil would rather spread false doctrine about God and the Godhead, and induce false feelings with reference to any one of them, than almost any other thing he could do. The creeds of Christendom illustrate perfectly what Lucifer wants so-called Christian people to believe about Deity in order to be damned.
These creeds codify what Jeremiah calls the lies about God (see Jeremiah 16:19; 23: 14–32). They say he is unknown, uncreated, and incomprehensible. They say he is a spirit, without body, parts, or passions. They say he is everywhere and nowhere in particular present, that he fills the immensity of space and yet dwells in the hearts of men, and that he is an immaterial, incorporeal nothingness. They say he is one-god-in-three, and three-gods-in-one who neither hears, nor sees, nor speaks. Some even say he is dead, which he might as well be if their descriptions identify his being.
These concepts summarize the chief and greatest heresy of Christendom. Truly the most grievous and evil heresy ever imposed on an erring and wayward Christianity is their creedal concept about God and the Godhead!
For more information, see The Mormon Mirage 3rd Edition: A Former Member Looks at the Mormon Church Today (Zondervan, 2009). Also available as an audiobook and as an expanded-text E-book for Nook, Kindle and other reading devices.