Musnad Ahmad 1099:5

Abu Sa’id, the freed slave of Banu Hashim, narrated to us, Mahdi ibn ‘Imran al-Mazini narrated to us, he said: I heard Abu al-Tufayl, and he was asked: "Did you see the Messenger of Allah, may Allah bless him and grant him peace?" He said: "Yes." It was said: "Did you speak to him?" He said: "No, but I saw him set out to such-and-such a place, and with him was ‘Abdullah ibn Mas’ud and some of his companions, until he came to a spacious house. He said: 'Open this door.' It was opened, and the Prophet, may Allah bless him and grant him peace, entered, and I entered with him. There was a velvet cloth in the middle of the house. He said: 'Lift this velvet cloth.' They lifted the velvet cloth, and there was a one-eyed boy under the velvet cloth. He said: 'Stand up, O boy.' The boy stood up. He said: 'O boy, do you bear witness that I am the Messenger of Allah?' The boy said: 'Do you bear witness that I am the Messenger of Allah?' He said: 'Do you bear witness that I am the Messenger of Allah?' The boy said: 'Do you bear witness that I am the Messenger of Allah?' The Messenger of Allah, may Allah bless him and grant him peace, said: 'Seek refuge in Allah from the evil of this,' twice."