Nature and significance
The ancient Greeks saw in Zoroastrianism the archetype of the dualistic view of the world and of man’s destiny. Zoroaster was supposed to have instructed Pythagoras in Babylon and to have inspired the Chaldean doctrines of astrology and magic. It is likely that Zoroastrianism influenced the development of Judaism and the birth of Christianity. The Christians, following a Jewish tradition, identified Zoroaster with Ezekiel, Nimrod, Seth, Balaam, and Baruch, and even, through the latter, with Christ himself. On the other hand, Zoroaster, as the presumed founder of astrology and magic, could be considered the arch-heretic. In more recent times the study of Zoroastrianism has played a decisive part in reconstructing the religion and social structure of the Indo-European peoples.
Though Zoroastrianism was never, even in the thinking of its founder, as aggressively monotheistic as, for instance, Judaism or Islām, it does represent an original attempt at unifying under the worship of one supreme god a polytheistic religion comparable to those of the ancient Greeks, Latins, Indians, and other early peoples.
Its other salient feature, namely dualism, was never understood in an absolute, rigorous fashion. Good and Evil fight an unequal battle in which the former is assured of triumph. God’s omnipotence is thus only temporarily limited. In this struggle man must enlist because of his capacity of free choice. He does so with his soul and body, not against his body, for the opposition between good and evil is not the same as the one between spirit and matter. Contrary to the Christian or Manichaean (from Manichaeism—a Hellenistic, dualistic religion founded by the Iranian prophet Mani) attitude, fasting and celibacy are proscribed, except as part of the purificatory ritual. Man’s fight has a negative aspect, nonetheless: he must keep himself pure; i.e., avoid defilement by the forces of death, contact with dead matter, etc. Thus Zoroastrian ethics, although in itself lofty and rational, has a ritual aspect that is all-pervading. On the whole, Zoroastrianism is optimistic and has remained so even through the hardship and oppression of its believers.