Musnad Abu Ya'la al-Mawsili 149:26

'Abd al-A'la narrated to us: I read to Malik ibn Anas, from Ibn Shihab, from 'Urwah, from 'A'ishah, the wife of the Prophet, that she said: "He was never given a choice between two matters except that he chose the easier of the two, as long as it was not a sin. If it were a sin, he would be the furthest of people from it. And the Messenger of Allah (may Allah bless him and grant him peace) never took revenge for his own self, unless a sanctity of Allah was violated, in which case he would take revenge for the sake of Allah."