Musnad Ahmad 5:755

'Affan narrated to us—I think he said from Abu 'Awanah, from Khalid ibn 'Alqamah, from 'Abd Khayr—who said: I came to 'Ali, may Allah be pleased with him, and he had already prayed. He called for water for purification. We said: "What is he doing with the water for purification? He has already prayed; what does he want?" [We thought] perhaps he wanted to teach us. He was brought a basin and a vessel. He lifted the vessel and poured [water] over his hand, and he washed it three times. Then he dipped his hand into the vessel and rinsed his mouth and sniffed water into his nose three times. He rinsed his mouth and sniffed water into his nose from the [same] palm from which he had taken [the water]. Then he washed his face three times, and washed his right hand three times, and his left hand three times. Then he placed his hand into the water and wiped his head one time. Then he washed his right foot three times and his left foot three times. Then he said: "Whoever is pleased to know the purification of the Messenger of Allah, may Allah bless him and grant him peace, then it is this."