Sigils are mystical symbols used for the invocation of spirits. They are usually used in conjunction with prayer, incantations or meditation to invoke the power of the spirit they represent. The Archangel sigils come from the ancient book "The Grimoire of Armadel" which contains sigils and invocations used to call forth the power of the Archangels. The sigil of the Archangel Michael is used to invoke his strength and protection. Michael is the spirit who guided the prophet Elisha in all his actions and is regarded as the protector of all kingdoms. Michael is considered to be the most powerful spirit after God himself and led the forces of heaven in their triumph over the powers of hell. The writings of King Solomon indicate that the sigil of the Archangel Michael must be used to invoke his spirit on a Sunday evening.