Sahih Muslim
The Book of Virtue, Good Manners and Joining of the Ties of Relationship (Kitab Al-Birr was-Salat-I-wal-Adab)
Book Number: 032 / Hadith Number: 6352
Abu Huraira reported Allah's Messenger (may peace be upon him) as saying: When a person says that people are ruined he is himself ruined. Abu Ishaq said: I do not know whether he said" ahlakahum or ahlakuhum.