Sahih Muslim
The Book of Jihad and Expedition (Kitab Al-Jihad wal-Siyar)
Book Number: 019 / Hadith Number: 4418
It has been narrated on the authority of 'Abdullah who said: It appeared to me as if I saw the Messenger of Allah (may peace be upon him) (and heard him) relate the story of a Prophet who had been beaten by his people, was wiping the blood from his face and was saying. My Lord, forgive my people, for they do not know.