Musannaf Ibn Abi Shayba 27:322

Abu Dawud Umar ibn Sa'd narrated to us, from Badr ibn Uthman, from Ubayd Allah ibn Marwan, from Abu A'isha, from Ibn Umar, who said: The Messenger of Allah (may Allah bless him and grant him peace) came out to us one morning and said: "I have just seen as if I were given the keys and the scales. As for the keys, they are these keys, and as for the scales, they are those with which you weigh." "Then I was placed in a pan, and my nation was placed in a pan, and I outweighed them. Then Abu Bakr was brought, and he outweighed them. Then Umar was brought, and he outweighed them. Then Uthman was brought, and he outweighed them. Then it was raised." He said: A man said to him, "So where are we?" He said: "Where you have placed yourselves."