Musnad Ahmad 30:1347

Ya'qub narrated to us, he said: My father narrated to us, Salih narrated to us, from Ibn Shihab, from 'Ubayd Allah ibn 'Abd Allah, from Abu Hurayrah, from the Messenger of Allah (may Allah bless him and grant him peace), who said: "There was a man who used to lend to people, and he would say to his servant: 'When you come to one in difficulty, overlook it for him, perhaps Allah will overlook it for us.' So he met Allah, and He overlooked it for him."