Al-Qasim al-Shami (may Allah have mercy on him) narrates that a freed slave-woman of his, called Umm Hashim, seated him behind a curtain with an inkpot and a pen, and sent for Sayyiduna Abu Umamah (may Allah be pleased with him) and asked him about the hadith he narrated from the Messenger of Allah (peace and blessings be upon him) concerning ablution. He said: I heard the Messenger of Allah (peace and blessings be upon him) say: "Whoever stands up to perform ablution and washes his hands, the sins come out from his hands; then when he rinses his mouth, the sins come out from his mouth; then when he blows out his nose, the sins come out from his nose; and so on until he washes his feet. Then if he goes out to an obligatory prayer, it is for him like an accepted Hajj; and if he goes out to a voluntary prayer, it is for him like an accepted Umrah."
Hadith Referenceالمعجم الكبير للطبراني / باب الصاد / 7944