Musnad Abu Ya'la al-Mawsili 3:149

Bandar Muhammad ibn Bashar narrated to us, Muhammad narrated to us, Shu'bah narrated to us, from 'Amr ibn Murrah, from 'Abdullah ibn Salamah, from 'Ali ibn Abi Talib, who said: I was complaining of an ailment, and the Messenger of Allah (peace and blessings of Allah be upon him) passed by me while I was saying: "O Allah, if my appointed time has arrived, then grant me rest; and if it is delayed, then raise me; and if it is a trial, then grant me patience." The Messenger of Allah (peace and blessings of Allah be upon him) said to him: "What did you say?" So he repeated it to him. He then struck him with his foot and said: "O Allah, grant him well-being; O Allah, heal him." He said: I did not complain of my pain after that.