The oldest and most revered tactic for avoiding the misery of guilt is religion. This tactic may be the most deceptive because it comes closest to the truth. It recognizes what the intellectual and physical strategies generally ignore: that the ultimate cause of guilt is that there is a righteous God whose will for his creatures is ignored or defied. It recognizes that under every pang of conscience in the human soul there is the silent, often unexpressed conviction, 'I have gone against God.' The means that religion has developed to deal with this guilt is to try to placate or appease God with good works or religious ritual. Religious people know they owe God a great debt for their disobedience. But they often make the terrible mistake of thinking they can pay it back through good works and the performance of religious duties.
John Piper