Under the Sasanian empire, from the third to the seventh century CE, Zoroastrianism became the state religion of Iran, and Ahura Mazda's cult was administered by a powerful priesthood, the magi, with fire temples endowed across the empire; Sasanian kings styled themselves as ruling by the grace of Ohrmazd. Within that same period a minority current called Zurvanism reworked the cosmology further, making Zurvan, personified Time, the father of both Ohrmazd and his adversary Ahriman as twin sons, a scheme the Gathas themselves do not contain and that mainstream Zoroastrian theology has generally rejected as a distortion of the god's uncreated primacy.
The winged figure now widely used as an emblem of Zoroastrianism, called the Faravahar, derives from the same disputed Achaemenid winged-disc imagery and was revived as a popular religious and national symbol mainly in the nineteenth and twentieth centuries, worn and displayed by Parsis and Iranian Zoroastrians alike, though its ancient meaning, whether fravashi, guardian spirit, royal glory, or the god himself, remains an open question rather than settled doctrine. The Arab conquest of Iran in the seventh century ended Zoroastrianism's status as a state religion and began the long migration and contraction that left the faith today a minority tradition, but Ahura Mazda remains, in both Iran and the diaspora, worshipped as the one uncreated Lord before the living flame.