It is narrated from Sayyiduna Abdullah bin Mas’ud (may Allah be pleased with him), who says that the Messenger of Allah (peace and blessings be upon him) taught him the Tashahhud and also instructed him to teach it to the people:
((All greetings, prayers, and pure words are for Allah. 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 Messenger.))