Musnad Ahmad 760:2

Abu Sa’id, the freed slave of Banu Hashim, narrated to us, Muhammad ibn Mutarrif Abu Ghassan narrated to us, Zayd ibn Aslam narrated to us, from ‘Ata’ ibn Yasar, from Abu ‘Abd Allah al-Sunabihi, that the Messenger of Allah (peace and blessings of Allah be upon him) said: "Whoever rinses his mouth and sniffs water into his nose, his sins fall out from his mouth and his nose. And whoever washes his face, his sins exit from the edges of his eyelids. And whoever washes his hands, they exit from his fingernails or from beneath his fingernails. And whoever wipes his head and his ears, his sins exit from his head or the hair of his ears. And whoever washes his feet, his sins exit from his toenails or from beneath his toenails. Then his steps to the mosque are a supererogatory act."