Proverbs 28:13 says, He who conceals his sins will not prosper, but whoever confesses and renounces them will find mercy.
A person will never succeed in life if they try to hide their sins. To cover one’s sins is either absolutely to disown them or to make excuses; a man who does this is never free from a burden of guilt, as the psalmist David says, “When I kept silence, my bones waxed old through my roaring all day long. For day and night thy hand was heavy upon me.
What was King David saying? I believe he was describing his state of mind before he could bring himself to confess his sin. His sin has overtaken his mind that he was tortured by remorseful pain, that his body bore the marks of his mental anguish.
The experience that David went through is what you and I will always experience if we do not repent of our sins to God. God is a merciful. God will forgive you. But in order for that to happen we must repent.