A common translation of the Latin hortative memento mori is "Remember thou shalt die."
I am not interested in a discussion of the Latin, nor of what the expression actually means in English. I am more interested in why English speakers chose the formulation "Remember thou shalt die" over "Remember thou wilt die," considering the implications of "shall" and "will" in English.
This thoroughly correct answer to a similar question definitely implies that "will" would be the right choice. --And yet Google has almost three thousand results for "Remember thou shalt die" (in quotes), and a mere two for "Remember thou wilt die."
Can anyone explain why this is? And: Which form is correct?
Related: The use of "will" in assumptions
N.B.: Mentions of "will" in this question refer to the future auxiliary, not to the verb "to will." Separately: I am not interested in answers which assert that "shall" and "will" are practically interchangeable these days.