Ali 'Imran 3:144

Wama muhammadun illarasoolun qad khalat min qablihi arrusulu afa-in mataaw qutila inqalabtum AAala aAAqabikum wamanyanqalib AAala AAaqibayhi falan yadurra Allahashay-an wasayajzee Allahu ashshakireen

Muḥammad is not but a messenger. [Other] messengers have passed on before him. So if he was to die or be killed, would you turn back on your heels [to unbelief]? And he who turns back on his heels will never harm Allāh at all; but Allāh will reward the grateful.

MuHammad is but a messenger, there have been messengers before him. So, if he dies or is killed, would you turn back on your heels? Whoever turns back on his heels can never harm Allah in the least. Allah shall soon reward the grateful.