Musnad Ahmad 26:179

Muhammad narrated to us, Shu'bah narrated to us, from Simak, who said: I heard 'Abd al-Rahman ibn 'Abd Allah narrating from his father—Shu'bah said: And I think he attributed it to the Messenger of Allah, peace and blessings of Allah be upon him—who said: "The likeness of the one who assists his clan in something other than the truth is like a camel that falls into a well, and he is pulling [it] by its tail."