Proverbs 20:9

Who can say, I have made my heart clean? No man can say that he hath made his own heart clean: but God can create in man a clean heart, as David expresses himself, Psalms 51:10, (on which see the note,) and can renew a right spirit within him; I am pure from my sin No man can render himself pure, either from the guilt of his past sins, or from the power or pollution of his corrupt inclinations and passions; but God surely, according to his promise, if we confess our sins, past and present, with humiliation, contrition, and godly sorrow for them, and rely on him, who gave himself for his church, that he might sanctify and cleanse it, and render it a glorious church without spot or wrinkle, or any such thing, can, and will freely and fully forgive us our sins, and cleanse us from all unrighteousness. He can justify us from all things, communicate to us a divine nature, and stamp his whole image on our souls.