Musnad Ahmad 32:1512

'Abd al-Wahhab narrated to us, Hisham informed us, from Qatadah, from Anas ibn Malik, who said: The Messenger of Allah (peace and blessings of Allah be upon him) came upon a man driving a sacrificial camel. He said: "Ride it." The man said: "O Messenger of Allah, it is a sacrificial camel." He said: "Ride it." He said: "It is a sacrificial camel." He said: "Ride it." He said: "It is a sacrificial camel." He said: "Ride it, woe to you," or "Woe unto you, ride it"—Hisham was uncertain.