It is narrated from Hazrat Abu Dharr (may Allah be pleased with him) that once I submitted in the court of the Messenger (peace and blessings be upon him), "O Messenger of Allah! Advise me with some counsel." The Noble Prophet (peace and blessings be upon him) said, "If you commit a sin, then perform a good deed afterwards which will erase that sin." I asked, "Is saying 'La ilaha illallah' included among good deeds?" The Noble Prophet (peace and blessings be upon him) replied, "This is the best of all good deeds."