D&C 64

The Lord taught the early members of the Church -

"I, the Lord, will forgive whom I will forgive, but of you it is required to forgive all men." (Doctrine and Covenants Section 64:10)

And then followed with -

"...ye ought to say in your hearts—let God judge between me and thee, and reward thee according to thy deeds." (Doctrine and Covenants Section 64:11)

But then He provides this important instruction to His priesthood leaders regarding -

"...him that repenteth not of his sins, and confesseth them not, ye shall bring before the church, and do with him as the scripture saith unto you, either by commandment or by revelation.
13 And this ye shall do that God may be glorified—not because ye forgive not, having not compassion, but that ye may be justified in the eyes of the law, that ye may not offend him who is your lawgiver—" (Doctrine and Covenants Section 64:12 - 13)

The Lord makes it clear that in the case of repentance, he requires discipline to be exercised by the priesthood so He is not offended, in the manner which the priesthood is instructed by commandment or as directed by revelation, so that all things are done according to His will -

"...not because ye forgive not, having not compassion, but that ye may be justified in the eyes of the law..."

Such discipline is done with love to help the sinner confess and repent of his sins. The Lord concludes with the seriousness of this responsibility -

"Verily I say, for this cause ye shall do these things." (Doctrine and Covenants Section 64:14)