Musnad Ahmad 26:15

Muhammad ibn Fudayl narrated to us, Khasif al-Jazari narrated to us, he said: Abu Ubaydah ibn Abdullah narrated to me, from Abdullah, he said: The Messenger of Allah, may Allah bless him and grant him peace, taught him the Tashahhud, and ordered him to teach it to the people: "The greetings are for Allah, and the prayers and the good things. Peace be upon you, O Prophet, and the mercy of Allah and His blessings. Peace be upon us and upon the righteous servants of Allah. I bear witness that there is no god but Allah, and I bear witness that Muhammad is His servant and His messenger."