Sahih Muslim Book 19, Hadith Number 4388.

Chapter : The battle of Hunain.

It has been narrated on the authority of Abu Ishaq who said: A man asked Bara’ (b. ‘Azib): Did you run away on the Day of Hunain. O, Abu Umira? He said: No, by Allah, The Messenger of Allah (may peace be upon him) did not turn his back; (what actually happened was that) some young men from among his companions, who were hasty and who were either without any arms or did not have abundant arms, advanced and met a party of archers (who were so good shots) that their arrows never missed the mark. This party (of archers) belonged to Banu Hawazin and Banu Nadir. They shot at the advancing young men and their arrows were not likely to miss their targets. So these young men turned to the Messenger of Allah (may peace be upon him) while he was riding on his white mule and Abu Sufyan b. al-Harith b. ‘Abd al-Muttalib was leading him. (At this) he got down from his mule, invoked God’s help, and called out: I am the Prophet. This is no untruth. I am the son of ‘Abd al-Muttalib. Then he deployed his men into battle array.