سنن النسائي

It was narrated from 'Abdullah As-Sunabihi that the Messenger of Allah (ﷺ) said: "When the believing slave performs Wudu' and rinses his mouth, his sins come out from his mouth. When he sniffs water into his nose and blows it out, his sins come from his nose. When he washes his face, his sins come out from his face, even from beneath his eyelashes. When he washes his hands, his sins come out from his hands, even from beneath his fingernails. When he wipes his head, his sins come out from his head, even from his ears. When washes his feet, his sins come from his feet, even from beneath his toenails. Then his walking to the Masjid and his Salah will earn extra merit for him."