The Star of David is a six-pointed star made up of two triangles superimposed over each other. In Judaism it is often called the Magen David, which means the "shield of David" in Hebrew. It doesn’t have any religious significance in Judaism but it is one of the symbols most commonly associated with the Jewish people. Many Jews wear jewelry with the Star of David as part of the design and the flag of Israel has a blue Star of David in the center. In many ways it has come to be a symbol of unity.
Origins of the Star of David
The origins of the Star of David are unclear. We do know that the symbol hasn't always been associated exclusively with Judaism, but was used by Christians and Muslims at various points in history. Sometimes it was even associated with King Solomon instead of King David.
The Star of David is not mentioned in rabbinic literature until the middle ages. It was during the latter part of this era that Kabbalists (Jewish mystics) began to associate the symbol with deeper spiritual meaning. The Star of David was eventually cemented as a Jewish symbol when it became a favorite architectural decoration on Jewish buildings and then during World War II, when Hitler forced Jews to wear a yellow Star of David as a "badge of shame." (Jews were also forced to wear identifying badges during the Middle ages, by the way, though not always a Star of David.)
In the past seventy-five years Jews have reclaimed the symbol, beginning with Zionists who gave the star national significance during the founding of Israel. Today the flag of Israel is a white banner with two horizontal blue lines that have a blue Star of David in the center.
There are many ideas about the symbolic meaning of the Star of David. Some Kabbalists thought that the six points represented God's absolute rule over the universe in all six directions: north, south, east, west, up and down. They also believed that the triangles represented humanity’s dual nature – good and evil – and that the star could be used as protection against evil spirits.
The structure of the star, with two overlapping triangles, has also been thought to represent the relationship between God and the Jewish people. The star that points up symbolizes God and the star that points down represents us here on earth. Yet others have noticed that there are twelve sides on the triangle, perhaps representing the Twelve Tribes.
The symbol’s association with King David comes mostly from Jewish legend. For instance, there is a midrash which says that when David was a teen he fought the enemy King Nimrod. David's shield was composed of two interlocking triangles attached to the back of a round shield and at one point the battle became so intense that that the two triangles were fused together. David won the battle and the two triangles were henceforth known as the Shield of David. This story, of course, is just one of many!