The following is from Judika Illes’s wonderful compendium Pure Magic: A Complete Course in Spellcasting
The Yoruba people of West Africa use the word orisha to name spirit powers. Anyone wishing to do extensive spirit work would do well to contemplate the structure of traditional Yoruba religion. The Yoruba are a monotheistic people; they have one supreme creator, Olodumare, who encompasses both male and female. Although Olodumare loves humans, we are not the center of the universe. Among Olodumare’s other creations was the concept of delegating. Olodumare created assorted spiritual beings, the orisha, each possessing its own department of interest, to assist in Earth’s harmonius operation. Just as there are orishas whose function it is to encourage agriculture or wilderness, so there are orishas who facilitate every aspect of human existence. Any area or interest that can be envisioned possesses an orisha who serves in a supervisory capacity.
Ogun, for instance, is the patron of metal. He takes care of those who are in close contact with the material: soldiers, jewelers, taxicab drivers. If you were worried about your son the soldier, you might direct your petition to Ogun.
Yemaya is the matron of women. If your personal obstacles fall under the general heading of “women’s troubles,” you’d petition Yemaya instead.
The most conservative count of orishas is 401, although only about forty are actively involved with humans on any sort of consistent, regular basis. Each orisha has various forms that they consistently assume. Each also possesses various preferences in food, fragrance, colors and gifts. These preferences are used as vehicles in two-way communication. Yemaya’s color is blue. To attract her notice, you might somehow prominently feature that color. She, in turn, might use the color to send a signal to you. It’s an eminently practical system and in the case of the Yoruba, still a living, vital one.
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