Leviticus 5:5

He that covereth his sins shall not prosper: but whoso confesseth and forsaketh them shall have mercy.

Then they shall confess their sin which they have done: and he shall recompense his trespass with the principal thereof, and add unto it the fifth part thereof, and give it unto him against whom he hath trespassed.

And Aaron shall lay both his hands upon the head of the live goat, and confess over him all the iniquities of the children of Israel, and all their transgressions in all their sins, putting them upon the head of the goat, and shall send him away by the hand of a fit man into the wilderness:

If they shall confess their iniquity, and the iniquity of their fathers, with their trespass which they trespassed against me, and that also they have walked contrary unto me;

And Joshua said unto Achan, My son, give, I pray thee, glory to the Lord God of Israel, and make confession unto him; and tell me now what thou hast done; hide it not from me.

For with the heart man believeth unto righteousness; and with the mouth confession is made unto salvation.

If we say that we have no sin, we deceive ourselves, and the truth is not in us. If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness. If we say that we have not sinned, we make him a liar, and his word is not in us.

And I prayed unto the Lord my God, and made my confession, and said, O Lord, the great and dreadful God, keeping the covenant and mercy to them that love him, and to them that keep his commandments;

Now therefore make confession unto the Lord God of your fathers, and do his pleasure: and separate yourselves from the people of the land, and from the strange wives. Then all the congregation answered and said with a loud voice, As thou hast said, so must we do.

Only acknowledge thine iniquity, that thou hast transgressed against the Lord thy God, and hast scattered thy ways to the strangers under every green tree, and ye have not obeyed my voice, saith the Lord.

He looketh upon men, and if any say, I have sinned, and perverted that which was right, and it profited me not;

I acknowledged my sin unto thee, and mine iniquity have I not hid. I said, I will confess my transgressions unto the Lord; and thou forgavest the iniquity of my sin. Selah.