Musannaf Ibn Abi Shayba 17:1272

Abu Khalid al-Ahmar narrated to us, from Ibn Ghaffar, from Abu Tamimah al-Hujaymi, from Abu Jurayy al-Hujaymi, who said: I came to the Messenger of Allah (peace be upon him) and said, "Are you the Messenger of Allah?" He said, "Yes." I said, "O Messenger of Allah, give me a command." He said, "Do not insult anyone." He said: So I did not insult anyone—neither a slave nor a free person, nor a sheep nor a camel.