*important new discovery* An early, dated Arabo-Islamic inscription from Ḥismā
that mentions the the prophet Muhammad by name. This one is dated to the end of 80AH[=January 700CE]. A mere 7 decades after his death A quick English translation below:

1) O Lord, bless Muḥammad [the Prophet] and accept his intercession on behalf of his community
2) And show us mercy through him in the Hereafter just as You have shown us mercy through him in this world
3) Written by Bakr ibn Abī Bakrah al-Asmlamī at the completion of year 80

sorry - read, " ... al-Aslamī ..."