How Can We Know We Are Forgiven?
President Harold B. Lee said, "When you have done all within your power to overcome your mistakes, and have determined in your heart that you will never repeat them again, then … peace of conscience [can come to you] by which you will know that your sins have been forgiven" (in "Law of Chastity Vital, Girls Told," Church News, Sept. 2, 1972, 7).
Once we have truly repented, Christ will take away the burden of guilt for our sins. We can know for ourselves that we have been forgiven and made clean. The Holy Ghost will verify this to us; He is the Sanctifier. No other testimony of forgiveness can be greater.
The Lord said, "He that repents and does the commandments of the Lord shall be forgiven" (D&C 1:32; emphasis added). And He said, "Come unto me, all ye that labour and are heavy laden, and I will give you rest" (Matthew 11:28). "Be faithful and diligent … and I will encircle thee in the arms of my love" (D&C 6:20).
And He declared, "Behold, he who has repented of his sins, the same is forgiven, and I, the Lord, remember them no more" (D&C 58:42).
Satan will try to make us believe that our sins are not forgiven because we can remember them. Satan is a liar; he tries to blur our vision and lead us away from the path of repentance and forgiveness. God did not promise that we would not remember our sins. Remembering will help us avoid making the same mistakes again. But if we stay true and faithful, the memory of our sins will be softened over time. This will be part of the needed healing and sanctification process. Alma testified that after he cried out to Jesus for mercy, he could still remember his sins, but the memory of his sins no longer distressed and tortured him, because he knew he had been forgiven (see Alma 36:17–19).
It is our responsibility to avoid anything that would bring back old sinful memories. When we continue to have a "broken heart and a contrite spirit" (3 Nephi 12:19), we may trust that God will "remember [our sins] no more."
"Point of Safe Return" - Elder Dieter F. Uchtdorf - April 2007 General Conference