Magen David, The Shield Of David

The following paragraph is from Dr. Asher Eder’s book The Star of David, which was published in 1987 in English in Jerusalem by Rubin Mass Ltd. The publication here is courtesy of Oren Mass
This version includes corrections and new materials that do not appear on the printed version

Many see the six-pointed Star as King David's personal monogram. They point out that the name David in Hebrew is דוד , daleth-wav-daleth, which can also be read "daleth & daleth" (as the letter wav can also mean "and"). In the old-Hebrew script, used from about the 10th to the 6th Century B.C.E., daleth had the form of a small triangle, similar to the old-Greek letter delta . The combination of the two daleth into a six-pointed star could well express David's achievement in uniting the Northern tribes of Israel (Joseph) with the Southern tribes of Judah (Yehudah)under their one God; or his great aspiration to unite the earthly and the heavenly under the Lord's sovereignty.
All this is underlined by the Hebrew name of the symbol: magen david, translated as "Shield of David" or "Star of David".
Jewish tradition holds that a six-pointed star was engraved on David's battle shield, and that the six outer triangles represented the six aspects of the Lord's spirit: "the spirit of wisdom and understanding, the spirit of counsel and might, the spirit of knowledge and of the fear of the Lord".
An old Arab tradition, probably deriving from this, says David's battle shield itself was in the shape of a six-pointed star.
The deeper inner meaning of these traditions is that David, both in his personal and in his national struggles "set the Lord always before him", and was shielded by Him even when he failed. Correspondingly, David's weapons in securing the country included both the Divine virtues and the sword of battle.