I said, "Messenger of Allah, give me some advice."He said, "When you commit a bad deed, follow it with a good deed and it will erase it."I said, "Messenger of Allah, is 'There is no god but Allah' among the good deeds?"He said, "It is the best of good deeds."
حدثنا أبو معاوية حدثنا الأعمش عن شمر بن عطية عن أشياخه
قلت يا رسول الله أوصني قال إذا عملت سيئة فأتبعها حسنة تمحها قال قلت يا رسول الله أمن الحسنات لا إله إلا الله قال هي أفضل الحسنات
No references are available.
Its chain of transmission is daif, due to the unidentified narrator from Abu Dharr, though it carries the status of a connected chain, for Shimr bin Atiya is trustworthy and accepted, narrating from a group of people. In any case, the hadith has already appeared at length under 21297 and 21251.