D&C 50

 The Lord taught - 

"Behold, verily I say unto you, that there are many spirits which are false spirits, which have gone forth in the earth, deceiving the world.

3 And also Satan hath sought to deceive you, that he might overthrow you."  (Doctrine and Covenants 50:2–3)

In that we encounter such "spirits" or influences among men, the Lord instructed - 

Wherefore, it shall come to pass, that if you behold a spirit manifested that you cannot understand, and you receive not that spirit, ye shall ask of the Father in the name of Jesus; and if he give not unto you that spirit, then you may know that it is not of God.

32 And it shall be given unto you, power over that spirit; and you shall proclaim against that spirit with a loud voice that it is not of God—

33 Not with railing accusation, that ye be not overcome, neither with boasting nor rejoicing, lest you be seized therewith."  (Doctrine and Covenants 50:31–33)