Musnad Ahmad 789:35

'Affan narrated to us, Mahdi ibn Maymun narrated to us, Abu al-Wazi', a man from the Banu Rasib, narrated to us, saying: I heard Abu Barzah say: The Messenger of Allah (peace and blessings of Allah be upon him) sent a messenger to a tribe among the Arab tribes regarding a matter—Mahdi did not know what it was. He said: So they insulted him and beat him. He complained of that to the Prophet (peace and blessings of Allah be upon him), and he said: "If you had come to the people of Oman, they would not have insulted you nor would they have beaten you."