Musannaf Ibn Abi Shayba 27:349

Hussayn ibn Ali narrated to us, from Za'idah, who said: Abd al-Malik said: Qabisah ibn Jabir narrated to me, saying: "I have not seen a man more knowledgeable of Allah, nor more reciting of the Book of Allah, nor more understanding of the religion of Allah, than Umar."