Abu Kamil Muzhaffar ibn Mudrik narrated to us, Zuhayr narrated to us, Abu Ishaq narrated to us, from Abdullah ibn Abi Basir, from his father, who said: I came to al-Madina and met Ubayy ibn Ka'b, so I said, "Abu al-Mundhir, tell me the most amazing hadith you heard from the Messenger of Allah, peace and blessings be upon him." He said: The Messenger of Allah, peace and blessings be upon him, led us (or led for us) the morning prayer, then turned to us with his face and said, "Is so-and-so present?" Then he mentioned the hadith...