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 6156
Imran b. Husain reported Allah's-Messenger (may peace be upon him) as saying: The best among you (are) the people (who belong to) my age. Then those next to them, then those next to them, then those next to them. 'Imran said: I do not know whether Allah's Messenger (may peace be upon him) said twice or thrice (the words:" Then next" ) after (saying) about his (own age but he then said): Then after them (after successors or those who would succeed them) would come a people who would give evidence before they are asked for it, and would be dishonest and not trustworthy, who would make vows but would not fulfil them, and would be significant in being bulky.