In Zoroastrianism/Mazdayasna, there is no deity like Ahura Mazda, the Wise Lord or “The Might of Wisdom.” Uncreated but the chief creator, wholly wise/wisdom manifest, all-good, and the upholder of Asha, Ahura Mazda is the deity most worthy of worship. Should one need to worship only one god (though there are many worthy of worship as well), Ahura Mazda would be that great deity. The Wise Lord is not omnipotent (in that Ahura Mazda is not every possible level of power) and has created a whole slew of divinities, including us, to aid in the maintenance of existence, the composing of creation, and the cosmic battle against Angra Mainyu and the Druj (the Lie).
All manifests from Ahura Mazda, but his most direct manifestations are the seven Amesha Spenta, the Boundless/Holy Immortals, who embody not just chief aspects of Ahura Mazda that we should emulate, but also maintain existence and rule on Ahura Mazda’s behalf. Traditionally, there are the six main Amesha Spenta, which embody Asha, Good Mind, Visionary Dominion, Creative Harmony, Wholeness, and Immortality. However, there exists a seventh Amesha Spenta known as Spenta Mainyu, the Creative/Holy Spirit. This Amesha Spenta is considered to be the closest to the purity of Ahura Mazda (as such, is usually represented as heading the Amesha Spenta) and is tasked with directly combating Angra Mainyu, the Destructive/Decaying Spirit.
The Amesha Spenta, in turn, have various Yazata (gods that have chosen The Good) to aid them in their maintenance of existence, the composing of creation, and to combat the forces of the Druj. These gods can belong to any pantheon, not just the traditional Zoroastrian one, just as any person can be good despite their origins. The idea that gods have free will and can be redeemed is also quite central to Zoroastrian thought, leading to Zoroastrianism being jokingly accused by some as being a divinity vetting agency. Some of the most well-known Yazata from the traditional pantheon include Mithra of Covenants, Sraosha of Conscience, Verethragna of Victory, and Anahita of the Waters. The Yazata are an equal bind with no set leadership or structure save for working towards the will and harmony of Ahura Mazda and the Amesha Spenta.
Those gods who have chosen to be against The Good are known as Daevas, who have sacrificed a portion of their divinity in order to rebel in the most noxious and foolish ways. They are headed in utter ignorance and confusion by Angra Mainyu and may be redeemed eventually, as even the ignorant have a chance of finding Truth. Ahura Mazda, being all good, has no plans to let them suffer in their own malice and plans to purify them once the frashokereti (the making perfect of existence) is complete if they have not chosen The Good already.
All conscious beings (including Humans) are considered lesser divinities and even a form of Yazata if they choose that path. Humans can indeed achieve apotheosis in this sense by maintaining the Threefold Path of Asha (Good Thoughts, Good Words, Good Deeds) and working towards the frashokereti, as is their mission as divinities made manifest. Humans, just like the rest of the Yazata, can confuse themselves in the worst ways (as we all well know) and become Daeva if they do foolishly choose this path. This is the worst of choices as instead of venturing into the House of Song after “death” to compose and inspire creation as is your Yazatic birthright, you fall into the House of Lies to plot and plan your rebellion with your dark comrades in utter confusion and ignorance, hurting yourself and others continuously in your malice.
There are a variety of intelligent beasts and beings, such as the Simurgh, but most are considered Yazata and not a separate category. Of course, they also have free will and can choose to serve the Daeva, as in the sad case of Azi Dahaka. Beasts without consciousness are viewed as being good and under our care, but there are beasts classified as noxious and tainted by Angra Mainyu (mosquitos are my top favorite to point out here) that must be changed to be good again through our advances in science and, if necessary, eradication.
-P.V.
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