Evocation is the act of calling or summoning a spirit, demon, god or other supernatural agent, in the Western mystery tradition. Comparable practices exist in many religions and magical traditions. Evocation in the Western mystery tradition and Edward Kelly evoking a spirit]]The first use of the term evocation was for the religious/magical practice of calling the tutelary deities of a city out of it so attackers could succeed in their conquest. The deity in question was promised worship by the attackers in the future. The calling forth of spirits was a relatively common practice in Neoplatonism, theurgy and other esoteric systems of antiquity. In contemporary western esotericism, the magic of the grimoires is frequently seen as the classical example of this idea. Manuals such as the Greater Key of Solomon the King, The Lesser Key of Solomon (or Lemegeton), the Sacred Magic of Abramelin the Mage