Musnad Abu Ya'la al-Mawsili 113:18

Abu Bakr ibn Abi Shaybah and Abu Khaythamah narrated to us, they said: Isma'il ibn 'Ulayyah narrated to us, from Khalid, from Abu Qilabah, who said: Anas said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Indeed, for every nation there is a trustworthy one, and our trustworthy one, O nation, is Abu 'Ubaydah ibn al-Jarrah."