This seems to be a real detriment to learning about what really goes on in the Mormon religion. But it is OK if it is done to keep the Church from looking bad.
Maybe the Leaders of the Church condone the act of murder and the like as long as lying that they are not can be used to keep it a secret.
Lying for the Lord
"What a thing it is for a man to be accused of committing adultery, and having seven wives, when I can only find one. I am the same man, and as innocent as I was fourteen years ago; and I can prove them all perjurers. I labored with these apostates myself until I was out of all manner of patience." - Joseph Smith 
"A half-truth presented as the whole truth is a complete untruth." - J.I. Packer
"Even sharing the truth can have the effect of lying when we tell only half-truths that do not give the full picture. We can also be guilty of bearing false witness and lying if we say nothing, particularly if we allow another to reach a wrong conclusion while we hold back information that would have led to a more accurate perception. In this case it is as though an actual lie were uttered." - Robert J. Matthews
"In matters of honesty, there are no shortcuts; no little white lies, or big black lies, only the simple, honest truth spoken in total candor... Being true is different than being honest.” - Gordon B. Hinckley
Lying for the Lord refers to the practice of lying to protect the image of and belief in the Mormon religion, a practice which Mormonism itself fosters in various ways. From Joseph Smith's denial of having more than one wife, to polygamous Mormon missionaries telling European investigators that reports about polygamy in Utah were lies put out by "anti-Mormons" and disgruntled ex-members, to Gordon B. Hinckley's dishonest equivocation on national television over Mormon doctrine, Mormonism's history seems replete with examples of lying. Common members see such examples as situations where lying is justified. For the Mormon, loyalty and the welfare of the church are more important than the principle of honesty, and plausible denials and deception by omission are warranted by an opportunity to have the Mormon
organization seen in the best possible light. This is part of the larger package of things that lead many to describe Mormonism as a cult. "Lying for the lord" is part of Mormonism's larger deceptive mainstreaming tactics, and conversion numbers would drastically lower if important Mormon beliefs were fully disclosed to investigators.
One Mormon blogger writes, "When I was a missionary, the church’s official Missionary Guide instructed missionaries to avoid providing direct answers or solutions to investigators' questions or concerns.” On his mission, he "fell back on rhetorical tricks or even outright denials."
And [God] had caused the cursing to come upon them, yea, even a sore cursing, because of their iniquity. For behold, they had hardened their hearts against him, that they had become like unto a flint; wherefore, as they were white, and exceedingly fair and delightsome, that they might not be enticing unto my people, the Lord God did cause a skin of blackness to come upon them. And thus saith the Lord God; I will cause that they shall be loathsome unto thy people, save they shall repent of their iniquities." (2 Nephi 5:21)
"Reason alone does not suffice." - Carl Jung
"To choose doubt as a philosophy of life is akin to choosing immobility as a means of transportation" - Yann Martel
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