Musnad Ahmad 33:1073

Surayj narrated to us, Abu 'Awanah narrated to us, from Abu Bishr, from Sulayman ibn Qays, from Jabir ibn Abdullah, who said: The Messenger of Allah, peace and blessings of Allah be upon him, fought [the tribe of] Muharib ibn Khasafah. A man from among them, who was called Ghawrath ibn al-Harith, came until he stood over the Messenger of Allah, peace and blessings of Allah be upon him, with a sword and said: "Who will protect you from me?" He said: "Allah." The sword fell from his hand, and the Messenger of Allah, peace and blessings of Allah be upon him, took it and said: "Who will protect you from me?" He said: "Be the best of those who take [retribution]." He said: "And do you bear witness that there is no god but Allah, and that I am the Messenger of Allah?" He said: "No, but I will make a covenant with you that I will not fight you, and I will not be with a people who fight you." So he let him go. He went to his people and said: "I have come to you from the presence of the best of people." When the time for prayer arrived, the Messenger of Allah, peace and blessings of Allah be upon him, performed the prayer of fear. The people were in two groups: one group facing their enemy, and one group prayed with the Messenger of Allah, peace and blessings of Allah be upon him. He prayed two rak'ahs with the group that was with him, and they departed and took the place of those who were facing their enemy. Then those who were facing their enemy departed and prayed two rak'ahs with the Messenger of Allah, peace and blessings of Allah be upon him. Thus, the Messenger of Allah, peace and blessings of Allah be upon him, had four rak'ahs, and the people had two rak'ahs each.