Discerning Good from Evil
Moroni 7:12–19
12 Wherefore, all things which are good cometh of God; and that which is evil cometh of the devil; for the devil is an enemy unto God, and fighteth against him continually, and inviteth and enticeth to sin, and to do that which is evil continually.
13 But behold, that which is of God inviteth and enticeth to do good continually; wherefore, every thing which inviteth and enticeth to do good, and to love God, and to serve him, is inspired of God.
14 Wherefore, take heed, my beloved brethren, that ye do not judge that which is evil to be of God, or that which is good and of God to be of the devil.
15 For behold, my brethren, it is given unto you to judge, that ye may know good from evil; and the way to judge is as plain, that ye may know with a perfect knowledge, as the daylight is from the dark night.
16 For behold, the Spirit of Christ is given to every man, that he may know good from evil; wherefore, I show unto you the way to judge; for every thing which inviteth to do good, and to persuade to believe in Christ, is sent forth by the power and gift of Christ; wherefore ye may know with a perfect knowledge it is of God.
17 But whatsoever thing persuadeth men to do evil, and believe not in Christ, and deny him, and serve not God, then ye may know with a perfect knowledge it is of the devil; for after this manner doth the devil work, for he persuadeth no man to do good, no, not one; neither do his angels; neither do they who subject themselves unto him.
18 And now, my brethren, seeing that ye know the light by which ye may judge, which light is the light of Christ, see that ye do not judge wrongfully; for with that same judgment which ye judge ye shall also be judged.
19 Wherefore, I beseech of you, brethren, that ye should search diligently in the light of Christ that ye may know good from evil; and if ye will lay hold upon every good thing, and condemn it not, ye certainly will be a child of Christ.
President George Q. Cannon said:
“Whenever darkness fills our minds, we may know that we are not possessed of the Spirit of God, and we must get rid of it. When we are filled with the Spirit of God, we are filled with joy, with peace and with happiness no matter what our circumstances may be; for it is a spirit of cheerfulness and of happiness.”
(Gospel Truth: Discourses and Writings of George Q. Cannon, sel. Jerreld L. Newquist, 2 vols. in 1 [1987], 17.)