This deity was originally called Ahura, «the lord,» and perhaps was connected to Mithra, the ruler of the time, before being elevated to the position of supreme being in the Persian religion by the prophet Zoroaster (see Zoroastrianism), and then he acquired the epithet Mazdah, «wise.»
Although the Indo-European pastoralists settled on the Iranian plateau derived their gods from the same pantheon as the Aryan conquers of India, the course of their religious development was entirely different.
While the Indian mind sought a unifying principle within a multiplicity of gods, in Persia the monistic tendency moved toward a universal monotheism under the direction of Zoroaster.
Fire was conceived to be the symbol of truth, which Ahura Mazdah bestowed on his followers. Light was opposed to darkness, and associated with truth and righteousness, asha.
In the myth of Atar, the fire of the sky and Ahura Mazdah’s son, there is a struggle with Azhi Dahaka, the three-headed dragon, who had usurped the earthly throne. His rule brought «need and misery, hunger and thirst, old age and death, mourning and lamentation, excessive heat and cold, and the intermingling of demons and men.»
Atar overcame the dragon, who was either consigned «to the bottom of the deep ocean» or chained on a high mountain. But Azhi Dahaka was destined to escape at the end of the world and destroy a third of humankind, before he was slain.
The divine fire, the spark indwelling in humankind, was the symbol of Ahura Mazdah, and in fire-temples the flame burns perpetually indicating his presence.
Ahura Mazdah is thought to be a god of prophetic revelation, the sole deity revealing himself to a traditionally polytheistic society not yet ready to receive the totality of his message.
The Zoroastrianism of the Persian kings accommodated existing religious practices, not least because it was controlled by a religious caste, the magi, with which it previously had nothing to do.
Once the followers of this prophet realized that the establishment on earth of a righteous kingdom was impossible in the present cycle of world ages, the way was open for Persian mythology to evolve a thorough dualism, with the source of evil being increasingly personified.
Finally two absolute rivals emerged: these were Ahriman, the master of deceit, and Ohrmazd, a contraction of Ahuramazdah, and in the ranks of their hostile host room was made for the gods whom Zoroaster tried to abolish. A.G.H.
Cotterell, Arthur, A Dictionary of World Mythology, New York, G. P. Putman’s Sons, 1980, p. 24
Boyce, Mary, Zoroastrians: Their Religious Beliefs and Practices, New York, Routledge, 2002, p. 11