In the scriptures, to deceive is to cause someone to believe something that is not true.

General Handbook: Serving in The Church of Jesus Christ of Latter-day Saints

38.8.40

Seeking Information from Reliable Sources

In today’s world, information is easy to access and share. This can be a great blessing for those seeking to be educated and informed. However, many sources of information are unreliable and do not edify. Some sources seek to promote anger, contention, fear, or baseless conspiracy theories (see 3 Nephi 11:30; Mosiah 2:32). Therefore, it is important that Church members be wise as they seek truth.

Members of the Church should seek out and share only credible, reliable, and factual sources of information. They should avoid sources that are speculative or founded on rumor. The guidance of the Holy Ghost, along with careful study, can help members discern between truth and error (see Doctrine and Covenants 11:12; 45:57). In matters of doctrine and Church policy, the authoritative sources are the scriptures, the teachings of the living prophets, and the General Handbook.

In consequence of evils and designs which do and will exist in the hearts of conspiring men in the last days, I have warned you, and forewarn you… (Doctrine and Covenants 89)

The Evil and Designs of Conspiring Men, Elder Delbert L. Stapley

Can we stand firm and true to the principles, ideals and standards of the gospel, or will we be so naive and unsuspecting as to fall into the traps of evil so cunningly planned and promoted by designing and conspiring men?

Possessing, as we do, the endowment of the Holy Ghost, if worthy, we are entitled to the gift of discernment to guide and help us avoid the pitfalls of scheming and designing men to trap and ensnare us.

I repeat, this warning concerning the evils and designs of conspiring men, although given in the revelation on the Word of Wisdom, has a much broader application than normally applied to its forbidden items, and, if rightly viewed, encompasses every field of human endeavor ... To narrow the meaning of this warning would make us vulnerable to the wicked designs of conspiring men who are not interested in the salvation of man but rather are interested in their own personal favor or gain.

The Savior gave warning that in these last days Satan will rage in the hearts of the children of men and will stir them up to anger against that which is good. "And many more things did the people imagine up in their hearts, which were foolish and vain; and they were much disturbed, for Satan did stir them up to do iniquity continually; yea, he did go about spreading rumors and contentions upon all the face of the land, that he might harden the hearts of the people against that which was good and against that which should come." (Helaman 16:22.)

Satan is alert and active. We must be more alert and perceptive of the false and insincere schemes of his agents among us.

In the Church, as elsewhere, we are at grips with the trying problems of evil. Therefore, we should be on guard constantly and so live as to discern the designs and intents of the wicked and not fall prey to their sinister schemes and motives. The Lord has been most kind and considerate by giving us this knowledge and warning by revelation. Will we heed the warning and not yield to Satan's powers and stratagems to deceive and to destroy us? Our peace our safety, our happiness is in listening to and following the teachings and instructions of the Lord's anointed.

I pray, my brothers and sisters, that we will have faith in the revelations and abide by the commandments, warnings, and admonitions which the Lord has given for our guidance, blessing, and exaltation, and with the eye of faith see through men's evil designs and with courage and wise purpose avoid them as a plague.

Deceivers

Satan—The Great Deceiver, Elder Marion G. Romney

The reality of the existence of both God and the devil is conclusively established by the scriptures and by human experience.

“And he became Satan, yea, even the devil, the father of all lies, to deceive and to blind men, and to lead them captive at his will, even as many as would not hearken unto my voice.” (Moses 4:3–4.)

Satan is evil: totally and always. He ever seeks to defeat the gospel plan and “destroy the souls of men.” (D&C 10:27.)

Satan is irrevocably committed to countering and overcoming the influence of the Spirit of Christ upon men. He is the representative, promoter, and advocate of that “opposition in all things” referred to by Lehi in his instructions to his son Jacob. (See 2 Ne. 2:11, 14–18.)

Satan’s methods are various, devious, and countless.

“… by every possible means he seeks to darken the minds of men and then offers them falsehood and deception in the guise of truth. Satan is a skillful imitator, and as genuine gospel truth is given the world in ever-increasing abundance, so he spreads the counterfeit coin of false doctrine. … [As] ‘the father of lies’ he has … become, through the ages of practice in his nefarious work,” such an adept “that were it possible he would deceive the very elect.” (Joseph F. Smith)

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That we may take the Holy Spirit for our guide, recognize Satan, his representatives and their works, and not be deceived by them, to the end that we may be partakers of the promised blessings, I humbly pray, in the name of Jesus Christ, our Lord. Amen.

Beware of false prophets, which come to you in sheep's clothing, but inwardly they are ravening wolves. (Matthew 7:15)

Secret combinations, especially the so-called "Gadianton robbers," figure prominently in the latter half of the Book of Mormon, contributing to the downfall of both Jaredites and Nephites. (In Joseph Smith's day, the word "combination" was essentially a synonym for "conspiracy.")

Gadianton robbers offer a textbook illustration of basic principles of guerrilla warfare — military techniques like those used by Vietnam (and in Afghanistan). They began as urban political assassins, but then, just as many such groups have done in the centuries since, withdrew into mountain redoubts from which they waged war against established governments.

In the Hearts of Conspiring Men, By M. Dallas Burnett. FCC ruled that broadcasting stations carrying cigarette commercials would have to “devote a significant amount of broadcast time” to anti-smoking commercials.

Fake Mormon news story goes viral, claiming the LDS Church has apologized for racism

In the fake story, published with a URL that was only one character off from the Church’s official website of mormonnewsroom.org, LDS Pres. Russell M. Nelson was quoted as issuing a full apology. The website was clearly calculated to exactly emulate the layout and design of the Church’s official website.