When it comes to a question of our forgiving other people, it is partly the same and partly different. It is the same because, here also, forgiving does not mean excusing. Many people seem to think it does. They think that if you ask them to forgive someone who has cheated or bullied them you are trying to make out that there was really no cheating or no bullying. But if that were so, there would be nothing to forgive. They keep on replying, “But I tell you the man broke a most solemn promise.” Exactly: that is precisely what you have to forgive. (This doesn’t mean that you must necessarily believe his next promise. It does mean that you must make every effort to kill every taste of resentment in your own heart — every wish to humiliate or hurt him or to pay him out.) The difference between this situation and the one in which you are asking God’s forgiveness is this. In our own case we accept excuses too easily; in other people’s we do not accept them easily enough.

C.S. Lewis (1898-1963) English writer and scholar [Clive Staples Lewis]
“On Forgiveness”