There is all the difference in the world between forgiving and excusing. Forgiveness says “Yes, you have done this thing, but I accept your apology; I will never hold it against you and everything between us two will be exactly as it was before.”But excusing says “I see that you couldn’t help it or didn’t mean it; you weren’t really to blame.” If one was not really to blame then there is nothing to forgive. In that sense forgiveness and excusing are almost opposites.- C.S. Lewis, The Weight of Glory, 178-81
Of course, in dozens of cases, either between God and man, or between one man and another, there may be a mixture of the two. Part of what seemed at first to be the sins turns out to be really nobody’s fault and is excused; the bit that is left over is forgiven. If you had a perfect excuse, you would not need forgiveness; if the whole of your action needs forgiveness, then there was no excuse for it. But the trouble is that what we call “asking God’s forgiveness” very often really consists in asking God to accept our excuses.
What leads us into this mistake is the fact that there usually is some amount of excuse, some “extenuating circumstances.” We are so very anxious to point these out to God (and to ourselves) that we are apt to forget the really important thing; that is, the bit left over, the bit which the excuses don’t cover, the bit which is inexcusable but not, thank God, unforgivable. And if we forget this, we shall go away imagining that we have repented and been forgiven when all that has really happened is that we have satisfied ourselves with our own excuses. They may be very bad excuses; we are all too easily satisfied about ourselves.
There are two remedies for this danger. One is to remember that God knows all the real excuses very much better than we do. If there are real “extenuating circumstances” there is no fear that he will overlook them. Often he must know many excuses that we have never thought of, and therefore, humble souls will, after death, have the delightful surprise of discovering that on certain occasions they sinned much less than they had thought. All the real excusing he will do.
What we have got to take to him is the inexcusable bit, the sin. We are only wasting time by talking about all the parts which can (we think) be excused. When you go to a doctor you show him the bit of you that is wrong – say, a broken arm. It would be a mere waste of time to keep on explaining that your legs and eyes and throat are all right. You may be mistaken in thinking so, and anyway, if they are really all right, the doctor will know that.
The second remedy is really and truly to believe in the forgiveness of sins. A great deal of our anxiety to make excuses comes from not really believing in it, from thinking that God will not take us to himself again unless he is satisfied that some sort of case can be made out in our favor. But that would not be forgiveness at all.
Real forgiveness means looking steadily at the sin, the sin that is left over without any excuse, after all allowances have been made, and seeing it in all its horror, dirt, meanness, and malice, and nevertheless being wholly reconciled to the man who has done it. That, and only that, is forgiveness, and that we can always have from God if we ask for it.