Not "You must kill unbelievers in Mecca," but you can, you are allowed to, but only after a grace period is over, and only if there's no other pact in place, and only if they try to stop you getting to the Kaaba, and only if they attack you first.
Nije, morate ubiti nevjernike u Meki, ali možete, dopušteno vam je, ali tek nakon perioda milosti i samo ako nema drugog dogovora i samo ako vas zaustave na putu do Kaabe, i samo ako vas oni prvi napadnu.