Here’s what I say in Unpacking Forgiveness:
If you are asking, “How can I forgive myself?” it is probably in reference to mistakes you have made in life. You know that your choices have caused yourself and others great pain. You want to know how you can move beyond your regret.
While is a good thing to want to move beyond your mistakes and the consequences they have reaped, there are fundamental problems with even raising this question. As I stress throughout Unpacking Forgiveness, forgiveness is something that must occur between two parties. In light of that truth, it makes no more sense to talk about forgiving yourself than it does to talk about shaking your own hand.
More important, our great need in life is not forgiveness from ourselves. Rather, we need God’s forgiveness. When it comes to regrets and lingering guilt, we need to ask God to forgive our sins, knowing that Christ already paid the penalty for sin on the cross. Paul talked about this very point in 2 Corinthians 7:10, when he said that godly grief brings about true repentance which leads to salvation. Nancy Leigh Demoss said, “Forgiveness isn’t something you can give yourself. It is something [God] has purchased for you.”
You might respond, “Okay, maybe you’re right. Maybe ‘forgiveness’ is not the word that I want to use. But how do I get past this? How do I move beyond my feelings of regret?” The short answer to that question is that you must be increasingly centered on the cross. You must live in the glory of the Gospel. The more you focus on Christ and the truth of his Gospel, the more you will find joy in your salvation and victory over guilt and bitterness.