Sayyiduna Uqbah bin Amir (may Allah be pleased with him) said: I heard the Messenger of Allah (peace and blessings be upon him) say: "The example of one who commits evil deeds and then does good deeds is like that of a man wearing a tight coat of mail that is choking him. Every time he does a good deed, one ring comes loose, then (with) another good deed another ring, until he comes out (free of the coat of mail) onto the ground."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 14856