Abu Hurairah (ra) narrated: The Messenger of
Allah (saw) said : “When a believer commits a
sin a black dot is engraved on his heart. If he
repents, gives up that evil deed and regrets,
then his heart is polished again; but if he
commits more errors, the dots will increase till
his heart is completely covered with it.” [At-
Tirmidhi, An-Nasa'i and IbnMajah]

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