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 6151
Abdullah reported: It was asked from Allah's Apostle (may peace be upon him) who amongst the people were the best. He said: (People) of my generation, then those next to them, then those next to them, then there would come a people whose evidence would precede their oath and their oath would precede their evidence. Ibrahim said: They forbade us to make vows and bear witness when we were too young.