"i want your sword and it would be trivial for me to just kill you take it from you now, but now i will leave and go wait or something and take it next time!"
that was so poorly executed it completely took me out of the moment. if anything it would be much easier for him to just take it now so he wont have to go back again to find mc and take the sword another time. he is clearly strong enough to trivially destroy mc and take the sword in seconds. that would also eliminate any future threat with no downsides