Abu Hurairah narrated that :
the Messenger of Allah said: “Verily, when the slave (of Allah) commits a sin, a block spot appears on his heart. When he refrains from it, seeks forgiveness and repents, his heard is polished clean. But if he returns, it increased until it cover his entire heart. And that is the ‘Ran’ which Allah mentioned: Nay, but on their hearts is the Ran which they used to earn.
