Musnad Abu Ya'la al-Mawsili 247:16

Hadba narrated to us, Mahdi bin Maymun narrated to us, Abu al-Wazi' Jabir bin 'Amr narrated to us, from Abu Barzah al-Aslami, who said: The Messenger of Allah (may Allah bless him and grant him peace) sent a man to one of the tribes of the Arabs regarding a matter—I do not know what it was—so they insulted him and beat him. He returned to the Prophet (may Allah bless him and grant him peace) and complained about that to him. He said: "But the people of Oman, if my messenger had come to them, they would not have insulted him nor would they have beaten him."