There were a great many of them, with varied functions and descriptions. Some were abstractions personified. There were males and females, denizens of earth and sky. Thirty-three of them were linked with the days of the month.
In "Mazdian Cosmology," Persian scholar Iraj Bashiri likens the Yazatas to the Christian archangels, with a pantheon of the Amesha Spentas 'immortal holy ones' (Spenta Mainyu [the all-pervading spirit of goodness and representative of Ahura Mazda], Vohu Manah, Asha Vahishta, Spenta Armaiti, Khshathra Vairya, Haurvatāt, and Ameretāt, [described in Zoroastrian treatment as Ahura Mazda's essences]), whom they assist, above them; and below them, the Farahvashi, serving as guardian angels.
Zoroastrian scholar Mary Boyce refers to the Amesha Spentas as also yazatas. Since those above the archangels would also be worthy of reverence, the word makes sense either way. The spiritual entities worthy of worship were contrasted with those who were not, the demons or daevas.
References:
- The Routledge Dictionary of Gods and Goddesses, Devils and Demons, by Manfred Lurker
- "Mazdian Cosmology", by Iraj Bahiri
- "Ormazd, or the Ancient Persian Idea of God," by A. V. Williams Jackson; The Monist, Vol. 9, No. 2 (January, 1899), pp. 161-178.
- "On Mithra's Part in Zoroastrianism," Mary Boyce; Bulletin of the School of Oriental and African Studies, Vol. 32,No. 1 (1969), pp. 10-34.
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