Musnad Abu Ya'la al-Mawsili 3:148

Muhammad ibn Bashar narrated to us, Muhammad ibn Ja'far narrated to us, Shu'bah narrated to us, from 'Amr ibn Murrah, who said: I heard 'Abdullah ibn Salamah say: I entered upon 'Ali, along with two men—a man from us and a man from Banu Asad, I believe. He sent them on a mission and said, "You two are strong men, so strive for your religion." Then he entered the lavatory and came out. He took a handful of water and wiped himself with it. Then he came and recited the Qur'an. He saw that we disapproved of that, so 'Ali said: "The Messenger of Allah (ﷺ) would go to the privy and relieve himself, then come out and eat bread and meat with us. Nothing would prevent him—or he perhaps said, 'nothing would hold him back'—from the Qur'an, except for major ritual impurity (janabah)."