The Star of David's hexagram is composed of two interlocked triangles. The triangle pointing downward represents the feminine principle (or Yoni Yantra), the upward pointing triangle is the male of fire energy. They are enclosed in a circle, a symbol of eternity and wholeness. The Hexagram originates in Tantric Hinduism, but is also known as Star of David, Shield of David or Solomon's Seal. It is mentioned in Jewish literature since the 12th century A.D. Legend has it that this symbol made King David invulnerable in battle and no weapons could pierce him. It became a symbol of Jewish faith in the 17th century.