Musannaf Ibn Abi Shayba 27:769

Abu al-Ahwas narrated to us, from Mansur, from Ibrahim, from Ubaydah, from Abdullah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "The best of my nation are the generation that are next to me, then those who are next to them, then those who are next to them. Then there will come a people whose testimony will precede their oath, and their oath will precede their testimony."