Musnad Ahmad 33:399

Abu al-Nadr narrated to us, from Ibn Abi Dhi'b, and Ibn Abi Bukayr, [who said] Ibn Abi Dhi'b informed us, from Sharhabil, from Jabir, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "For one of you to restrain his hand from the pebbles is better for him than a hundred she-camels, all of which have black pupils. But if one of you is overcome by the Shaytan, then let him perform a single wiping."