The Element Encyclopedia of Witchcraft: The Complete A-Z for the Entire Magical World - Judika Illes 2005
Spirit Working/Spirit Summoning
Spirit working is the art of communicating with spirits for spiritual and magical purposes. The difference between spirit working and ritual possession is that no possession is involved. Communication is between the spirit and the person; the person doing the summoning doesn’t become the venue from which the spirit communicates.
Spirit working is often accomplished via construction of altars: tableaux designed to attract the attention of a specific spirit. Thus an altar designed to honor the orisha Yemaya or attract her favor or attention would incorporate her sacred colors (blue and white), her sacred number (seven), and objects identified with her. Yemaya is an ocean spirit. A glass of salt water might be placed on the altar alongside seashells, sea glass or other gifts of the sea. Seven blue and white candles might be lit to call Yemaya, who might be symbolized on the altar by the image of a mermaid. Special foods or drink that the spirit allegedly favors would be placed on the altar as well.
Spirit working is among the most common forms of magic; it is very traditional magic.
The Inquisition regarded “spirit worship” (devotion to spirits) as especially dangerous because it encouraged the rise of “heretical sects.”
According to the Talmud, the reason spirits are usually invisible is that if we saw them all swarming through the air we’d probably die of terror.
There are an innumerable number of spirits. Every thing on Earth, every animal, creature, plant or object has at least one affiliated spirit, and so spirit working may be used to accomplish any purpose.