undoubtedly at first the six pointed like the five pointed served mainly for secret numerical speculations… In this image of six points it's possible to see as well a star emblem. Connecting this emblem to the name of David originates doubtless from the source of the messianic idea… As known the verse “there shall step forth a star out of Jacob”, in Numbers 24:17, was interpreted already on days of Hashmonean about the anticipated Messiah, and from here also the myth of the star in the new testament, that unquestionably originates from this ancient tradition. And more than that this interpretation takes place on the days of Bar Coziva who, on the basis of that verse, nicknames himself Bar Cochva (the son of the star), and to this nickname rabbi Akiva and his ardent students also agree. And it was quite natural to tie the same image of the star to the name of David, the father of the fathers of the Messiah. The star became the symbol of the Messiah, and in this way became also renowned as the emblem in the shield of King David. In other words the star in the shield of King David is the national emblem of the Hebrew people.
Every amulet and magical combination that we find now unquestionably had been copied from more ancient amulet because it is forbidden to change even one letter if you don’t want it to lose its power.Which means that Jews recognized the Magen David and used it in their amulets hundreds of years before it was found in the Genizah.
Dr. Gaster also notes that:
To our wonder it was also found in the British Museum on the margins of pages of Greek magic charms from the second or third century.
It’s a pity Dr. Gaster didn’t give us some more accurate details about these Greek magic charms, because I’d like to see them.
Dr. Gaster’s interpretation to the verse “there shall step forth a star out of Jacob” fits Uri Ofir’s findings in his research about the Jewish Origin of the Star of David where he says that Rashi and Ibn Ezra interpreted that Balaam prophesized in this verse about King David. These interpretations were certainly known to Dr. Gaster.