Musnad Ahmad 31:494

Zayd ibn al-Hubab narrated to us, Hammad ibn Zayd narrated to me, al-Mu'alla ibn Ziyad al-Mu'awali narrated to us, from al-'Ala' ibn Bashir al-Muzani, from Abu al-Siddiq al-Naji, from Abu Sa'id al-Khudri, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "I bring you glad tidings of the Mahdi. He shall be sent forth in my Ummah at a time of disagreement among the people and earthquakes. He will fill the earth with equity and justice, just as it was filled with oppression and tyranny. The dweller of the heaven and the dweller of the earth shall be pleased with him. Allah will fill the hearts of the Ummah of Muhammad with richness, such that no one will be in need of anyone else. Then a caller will call out: 'Who has a need for wealth?' A man will stand up and say: 'I.' It will be said to him: 'Go to the custodian'—meaning the treasurer—'and say to him: The Mahdi says to you: Give me.' He will go to the custodian and say that to him. It will be said to him: 'Scoop it up,' and he will scoop it up. When he secures it, he will say: 'I was the greediest of the Ummah of Muhammad in soul, or did that which sufficed them fail to suffice me?' He will remain for seven, eight, or nine years. Then there is no good in life, or in living, after him."