Musnad Abu Ya'la al-Mawsili 109:86

Abu Musa al-Harawi narrated to us, al-Mu'afa narrated to us, from Ibrahim ibn Yazid, from 'Ata', from Jabir, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Every act of kindness that one of you performs toward a rich person or a poor person is a charity for him on the Day of Resurrection."