Musnad Ahmad 32:979

'Abd al-Rahman ibn Mahdi narrated to us, from Hammad ibn Zayd, from Thabit, from Anas; and Abu Kamil narrated to us, Hammad ibn Zayd narrated to us, from Thabit, from Anas, who said: "The Messenger of Allah (peace and blessings of Allah be upon him) was the most handsome of people, the bravest of people, and the most generous of people." There was a panic in Medina, so the people went out toward the sound. The Messenger of Allah (peace and blessings of Allah be upon him) met them, having already preceded them, and he had investigated the cause of the panic, riding a horse belonging to Abu Talha that was bare, with no saddle upon it, and a sword was around his neck. He said: "Do not be alarmed." And he said regarding the horse: "We found it to be a sea—or: It is indeed a sea."