"If someone looks for the Shield of David among the Jewish symbols in antiquity, he may not find it. Although the legend is well known that in Biblical times king David in his wars had adorned his shield with a six-pointed star, it is without historical proof."
"We may conclude that since late antiquity the six-pointed star has been a universal, magic-astrological sign with no exclusive Jewish meaning, but with a specific magic adaptation within the context of Jewish cosmogony and mysticism. The sign may have represented the good angels, which were thought to be celestial beings. It was sent down from heaven to the mystic on earth, where it provided the owner with protective power over the demons...The sign was accompanied with incantations, eulogies, psalms as well as the mystical names of God and the angels....the hexagram became a protective sign against evil in general and, in the case of the popular use of amulets, served to protect the unborn child against demons. It also served the needs of the ordinary people and thus in medieval and early modern times it became a widely known symbol of magic and superstition."
"The first examples of the six-pointed star in Judaism originate from the seventh century B.C.E. A first Jewish adaptation of the hexagram together with its astro-magical meaning took place in the first centuries C.E. As we have no written documents on this process, but only archeological findings, we may assume that the adoption caused no hermeneutical problems, but instead was a rather natural development."
"The great Jewish philosopher and commentator Maimonides (1135 till 1204) criticized the use of magic signs on mezuzoth, from which we may conclude that not only the pentagram, but also the hexagram were already in the 12th century or earlier a widely used magic talisman."