Origin of the Commandment Plaque
The Commandment Plaque is a Magical Instrument ( 法器 Faqi ) frequently used in Daoist rituals of Fasts and Offerings ( 齋醮 Zhaijiao ). It originates from the Tiger Talisman used for giving orders by the armies in ancient China. The item "commandment plaque" in the Daoist Book of Accordance with Spirits ( 道書援神契 Daoshu Yuanshen Qi ) states: "it is recorded in the Rites of the Zhou ( 周禮 Zhouli ) that an ivory plaque is used for arousing armies to action. The copper Tiger Talisman of the Han dynasty is round in the upper part and square in the lower part with five characters inscribed on it, and is shaped like a dewdrop. At the back of the talisman is carved a sitting tiger and an inscription with the words: the Tiger Talisman is made like an ancient ivory plaque. Recent use of the Commandment Plaque for summoning generals takes this as its model".
The Commandment Plaques used in Daoism are usually made of wood or metal. They are rectangular lumps with pictures and characters carved or cast on all six sides. The Highest Clarity Numinous Treasure Golden Book of the Great Achievement of Aid and Salvation ( 上清靈寶濟度大成金書 Shangqing Lingbao Jidu Dacheng Jinshu ) of the Ming dynasty contains an illustration and text of the Commandment Plaque of the Five Thunders. On the front of the picture is a carving of a dragon brandishing a sword, and on the reverse side are the Talismanic Characters of the Thunder Commandment, which say: " the Right Commandment Plaque is made of jujube wood struck by lightning. It is five cun and five fen long, two cun and four fen wide, and five fen thick. It is made according to rules on auspicious days. The names of the Twenty-Eight Constellations are engraved on its four sides." The plaque is held in an embroidered bag. When Daoist priests perform rituals, they often strike the commandment plaque violently at the ritual altar when, in the name of the Heavenly Spirits or Celestial Masters, they give orders, summon wind and rain, convoke spirits and generals to descend to the ritual altar, escort the souls of the dead, or dispel evil spirits and control ghosts.