Musnad Ahmad 33:848

Muhammad ibn Ja‘far narrated to us, Shu‘bah narrated to us, from Abu Ishaq, that he heard Sa‘id ibn Abi Karb, or Shu‘ayb ibn Abi Karb, say: I heard Jabir ibn ‘Abd Allah, while he was upon a camel, saying: I heard the Messenger of Allah, peace and blessings of Allah be upon him, saying: "Woe to the heels from the Fire."