Abu Dawud Book 32, Hadith Number 4324.
Chapter : Not known.
Narated By AbuBakr : You people recite this verse “You who believe, care for yourselves; he who goes astray cannot harm you when you are rightly-guided,” and put it in its improper place.
Khalid’s version has: We heard the Prophet (PBUH) say: When the people see a wrongdoer and do not prevent him, Allah will soon punish them all. Amr ibn Hushaym’s version has: I heard the Apostle of Allah (PBUH) say: If acts of disobedience are done among any people and do not change them though the are able to do so, Allah will soon punish them all.