Surah 3

Surah 3:144

"Muḥammad is only a messenger. Messengers have already passed away before him. If he dies or is killed, will you turn back on your heels? Whoever turns back on his heels will not harm God at all. God will repay the thankful."

3.144 – Muhammad is only a messenger. Messengers have already passed away before him
This is the first appearance of the name Muhammad in the canonical progression of the Quran. Here Muhammad is “nothing but a messenger” who could die or be killed.
The context surrounding the verse calls to mind a military scene. There are battle wounds and “struggle” (vv. 120, 140, 143). The Quran mentions fighting and killing (vv. 146, 152). Muslim stories of Islamic origins associate 3.144 with the defeat of the Muslims in the battle of Uḥud.
The name Muḥammad appears only three other times in the Quran. This is striking, given that Muslims believe the Quran was revealed to Muhammad. All four occurrences are in the third person, declaring something about Muhammad, and never in the second person or direct address (“O Muhammad”). See the discussion of the four appearances of the name at 48.29.

- from The Quran with Christian Commentary: A Guide to Understanding the Scripture of Islam