Moreover the Messenger (peace and blessings of Allaah be upon him) taught it to his ummah, and he even taught it to Ibn Mas’ood, holding his hand between his own, so that he would remember this wording. He used to teach it to them as he used to teach them a soorah from the Qur’aan. And he knew that he was going to die, because Allaah said to him (interpretation of the meaning):
“Verily, you (O Muhammad) will die, and verily, they (too) will die”
[al-Zumar 39:30]
But he did not say: after I die, say “al-salaamu ‘ala al-nabi (peace be upon the Prophet)”, rather he taught them the tashahhud…