Musnad Ahmad 30:1687

Mu'awiyah ibn 'Amr narrated to us, he said: Za'idah narrated to us, from 'Asim, from Abu Salih, from Abu Hurairah, from the Prophet, peace and blessings of Allah be upon him, who said: "I saw myself at a well, drawing water with a bucket. Then Abu Bakr took it and drew a bucketful or two, and there was some weakness in his drawing, and may Allah have mercy on him. Then 'Umar took it, and it transformed in his hands into a large bucket, and he continued to draw until the people drank their fill and watered their camels until they rested. I have never seen a master of the people draw water as skillfully as 'Umar."