THE DEBATE SET OFF BY THIS POST IS UNNECESSARY AND BASED ON A FAULTY TRANSLATION
The poster posted the English translation of this quote, which was made in England in 1879 and is (as I guessed) mangled to make it sound like something relevant to the debate between protestants and Catholics.
Fortunately, the same website they linked has the original Latin:
Damasci sancti Petri Mavimeni, qui, cum diceret Arabibus quibusdam, ad se aegrotum venientibus: “Omnis qui fidem Christianam catholicam non amplectitur, damnatus est, sicut et Mahumet, pseudopropheta vester,” ab illis est necatus.
Note:
1. The quote uses small c catholic (Christianam catholicam), which makes sense because the quote is from before the schism; it’s the same word catholicam we find in the creed;
2. Mavimeni doesn’t say “religion”. He says faith.
So the correct translation is “whoever doesn’t accept the catholic Christian faith” which I’m pretty sure even Martin Luther would agree with.
Damasci sancti Petri Mavimeni, qui, cum diceret Arabibus quibusdam, ad se aegrotum venientibus: Omnis qui fidem Christianam catholicam non amplectitur, damnatus est, sicut et Mahumet, pseudopropheta vester, ab illis est necatus.
Thanks for your post: I hadn't thought to look there for the original Latin, even though I was considering looking for it somewhere and was all this time forgetting the most obvious place.
THE DEBATE SET OFF BY THIS POST IS UNNECESSARY
Sic transit gloria fori.