مسند أحمد

It was narrated from Humran, the freed slave of `Uthman (رضي الله عنه) that `Uthman did wudoo’ in al-Maqa`id, he washed each part of the body three times and said: I heard the Messenger of Allah (ﷺ) say: “Whoever does wudoo’ as I have done then gets up to pray, his sins will fall away, i.e., from his face, his hands, his feet and his head.`