Musannaf Ibn Abi Shayba 27:289

Abu Mu'awiyah narrated to us, from al-A'mash, from Abu Salih, from Abu Hurayrah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "No wealth has benefited me as the wealth of Abu Bakr has benefited me." Abu Bakr wept and said: "Am I and my wealth anything other than for you, O Messenger of Allah?"