"I leave you in peace. The peace only my teachings can provide for you and not as the world claims to find peace. Do not be confused nor fearful, You heard me say to you, I am leaving, and will return again. If you loved me, you would be rejoicing because I told you I am returning to my Father's realm. My Father dwells in the highest heaven. I foretell you about what remains for me to accomplish so that you are not confused as it happens. When the coming events unfold I will not be able to explain it further as it occurs. The prince of darkness will not overcome me, but he can overcome you if you are confused and fearful." (TSJ Chpater 10, Cross Ref. John 14)In D&C 6 (LE) it was explained this way. It ties "peace" to receiving "I have told you things which no man knoweth".
22 Verily, verily, I say unto you, if you desire a further witness, cast your mind upon the night that you cried unto me in your heart, that you might know concerning the truth of these things.In D&C 8 (LE) it is explained this way.
23 Did I not speak peace to your mind concerning the matter?What greater witness can you have than from God?
24 And now, behold, you have received a witness; for if I have told you things which no man knoweth have you not received a witness?
8 But, behold, I say unto you, that you must study it out in your mind; then you must ask me if it be right, and if it is right I will cause that your bosom shall burn within you; therefore, you shall feel that it is right.To gain peace is to gain understanding of the Lords gospel. Glad tidings of great joy. It is through that knowledge that we can prevent us from being overcome, gain understanding, and prevent us from falling into confusion.
9 But if it be not right you shall have no such feelings, but you shall have a stupor of thought that shall cause you to forget the thing which is wrong; therefore, you cannot write that which is sacred save it be given you from me.