The Book Pertaining to the Merits of the Companions (Allah Be Pleased With Them) of the Holy Prophet (May Peace Be Upon Him) (Kitab Al-Fada'il Al-Sahabah)
Muslim :: Book 31 : Hadith 5894
Abdullah b. 'Umar reported Allah's Messenger (may peace be upon him) as saying: I saw (in a dream) as if I was drawing water with a leathern bucket on a wooden pulley. There came Abu Bakr and he drew out a bucketful or two and as he drew out, some weakness (was perceived in it) (may Allah, the Exalted and Glorious, forgive him). Then Umar came in order to serve water -and the bucket was changed into a large leather bucket and I did not see such a wonderful man amongst persons (drawing water) and he went on serving water to the people until they were fully satisfied and then went to their resting places.