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: 6196
Nawwas b. Sim'an al-Ansiri reported: I asked Allah's Messenger (may peace be upon him) about virtue and vice. He said: Virtue is a kind disposition and vice is what rankles in your heart and that you disapprove that people should come to know of it.