Musnad Ahmad 626:61

'Abd al-Razzaq and Muhammad ibn Bakr narrated to us, they said: Ibn Jurayj informed us, he said: Ibn Shihab narrated to me, from the hadith of 'Abbad ibn Ziyad, that 'Urwah ibn al-Mughirah ibn Shu'bah informed him that al-Mughirah ibn Shu'bah informed him: That he went on a military expedition with the Messenger of Allah, peace and blessings of Allah be upon him, the expedition of Tabuk. Al-Mughirah said: The Messenger of Allah, peace and blessings of Allah be upon him, went out to relieve himself before the dawn prayer, and I carried a water skin with me. When the Messenger of Allah, peace and blessings of Allah be upon him, returned to me, I began to pour from the water skin onto his hands, and he washed his hands three times. Then he washed his face. Then he went to take his cloak off his arms, but the sleeves of his cloak were tight, so he inserted his hands into the cloak until he brought his arms out from beneath the cloak, and he washed his arms up to the elbows. Then he wiped over his leather socks, then he came forward. Al-Mughirah said: I came forward with him until we found that the people had already put forward 'Abd al-Rahman ibn 'Awf to lead them in prayer, and he had already completed one of the two rak'ahs. 'Abd al-Razzaq and Ibn Bakr said: So he prayed the last rak'ah with the people. When 'Abd al-Rahman gave the taslim, the Messenger of Allah, peace and blessings of Allah be upon him, stood up to complete his prayer. That alarmed the Muslims, and they glorified Allah (said "SubhanAllah") a great deal. When the Messenger of Allah, peace and blessings of Allah be upon him, finished his prayer, he turned to them and said: "You have done well," or "You have done correctly," commending them for having prayed the prayer at its proper time.