Musnad Ahmad 501:1

'Abd al-Samad narrated to us, 'Umar ibn Hamzah narrated to us, 'Ikrimah ibn Khalid narrated to us, he said: A man spoke ill of the Banu Tamim in his presence, so he took a handful of pebbles to pelt him with. Then 'Ikrimah said: So-and-so from the companions of the Prophet, may Allah bless him and grant him peace, narrated to me: That the Tamim were mentioned in the presence of the Messenger of Allah, may Allah bless him and grant him peace, and a man said: "This tribe of Tamim has been slow regarding this matter." The Messenger of Allah, may Allah bless him and grant him peace, looked at the Muzaynah and said: "No people have been slower than these are among them." And a man said one day: "These people of Tamim have been slow with their charity." He said: Then red and black camels belonging to the Banu Tamim arrived, and the Prophet, may Allah bless him and grant him peace, said: "These are the camels of my people." And a man spoke ill of the Banu Tamim in the presence of the Messenger of Allah, may Allah bless him and grant him peace, one day, so he said: "Do not say anything about the Banu Tamim except good, for they are the people with the longest spears against the Dajjal."