There are 3 people who know about your wrong doings, the devil, you and God. The devil will always use your sins to stop you from reaching out to God. Matthew 5:25 Agree with your adversary quickly, while you are on the way with him, lest your adversary deliver you to the judge, the judge hand you over to the officer, and you be thrown into prison. God want you to come to Him with your weakness but the devil uses your weaknesses to move you away from God.
When you repent, you free yourself from him. The devil no longer has a leg to stand on. He can not accuse you of anything.