A minister once introduced a message on Psalm 51 by saying:
"Tonight we come to something which if you have it, even if your life completely blows up, it can be repaired. If you've got it, no matter how broken your life, no matter how severely broken, it can be made whole. But, I'm afraid to name it, because when you hear it, when I use the English word, I'm afraid a lot of you will say, ‘O, that. I already know about that.’†The word, the thing that he was talking about is repentance. That's what Psalm 51 is about: life renewal through radical repentance.