Musannaf Ibn Abi Shayba 13:3012

Abu Bakr narrated to us, he said: Yazid bin Harun narrated to us, he said: Dawud bin Abi Hind informed us, from al-Sha’bi, from Shurayh, who said: I have never exerted myself against the uvula of an opponent, nor have I prompted him with his argument.