Abu Dawud
General Behavior
Book Number: 036 / Hadith Number: 4862
Narated By AbuBarzah al-Aslami : The Prophet (pbuh) said: O community of people, who believed by their tongue, and belief did not enter their hearts, do not back-bite Muslims, and do not search for their faults, for if anyone searches for their faults, Allah will search for his fault, and if Allah searches for the fault of anyone, He disgraces him in his house.