Zoroaster (active 1st millennium B.C.) was a prophet of ancient Iran and the founder of the Iranian national religion. Zoroastrianism is ranked with Judaism, Christianity, and Islam among the higher religions originating in the Middle East.
The dates given for Zoroaster by ancient and modern writers differ considerably. The more sober authors have placed him between 1000 and 600 B.C. The latter date conforms to the tradition of the Zoroastrians themselves, who regard Zoroaster as having revealed his religion 258 years before Alexander the Great conquered Iran in 331 B.C. The main sources for the life and career of Zoroaster are the Avesta, the sacred book of the Zoroastrians, the oldest and most reliable source; later Zoroastrian literature, among which Denkart, an encyclopedic work in Middle Persian, stands out; and non-Zoroastrian works, which include Persian, Arabic, Armenian, and classical histories.
Zoroaster was known among the classic writers chiefly as the initiator of the Magian belief and was regarded as a great sage. The Magians were a priestly class of ancient Iran and were the repository of Persian religious lore and learning. Zoroaster is first mentioned by a Lydian historian of the 5th century B.C. Plato mentions Zoroaster in Alcibiadesin connection with Magian teachings, and Plutarch gives a summary of Zoroaster's religious doctrine and cosmology.
Only the earliest part of the Avesta was composed by the prophet himself. This portion is called Gathas (Hymns). The other parts, which include hymns, prayers, litanies, and religious law, were written over a period of perhaps several centuries. The dialect of the Gathas is slightly different from the rest of the Avesta and somewhat more archaic. The language of the Avesta has long been dead. Ambiguities in a number of Avestan passages have given rise to differences of interpretation and have made some aspects of the prophet's life the subject of heated controversy.
A brief sketch of the prophet's career, however, may be gleaned from the Gathas. In these metrical preachings Zoroaster appears as a human and plausible figure, devoid of many of the mythical and legendary details found in later literature. According to the Gathas, Zarathushtra (as Zoroaster is called in the Avesta), son of Pourushaspa and from the house of Spitama, is a preacher inspired by and in communion with his Lord, Ahura Mazda. He is distressed at the spread of wickedness and the neglect of truth. He tries to awaken his people to the importance of righteousness and warns them against following false leaders practicing animal sacrifice, mistreating the cattle, and permitting the drinking of homa (an intoxicating drink) in the ritual. His exhortations, however, are not heeded. He meets with the indifference of his people and the opposition of the communities' religious leaders. He puts his trust in his Lord, with whom he holds a number of discourses. He seeks the active help and guidance of Ahura Mazda and eventually succeeds in converting King Vishtaspa, who then accords him protection and support.
In later Zoroastrian literature, Zoroaster's life becomes wrapped in marvels and miraculous events. In these sources he is presented as a native of Media in western Iran. Through Doghdova, his mother, he inherits farnah, the Divine Glory, without which no Persian king or prophet could succeed. According to the seventh book of the Denkart, which gives an account of the miraculous birth and life of the prophet, Ahura Mazda himself intervenes in the selection of the essence of Zoroaster's body and soul from celestial spheres.
Sorcerers and demons, perceiving Zoroaster as a threat to their interests, make several attempts on his life, but he is protected by Ahura Mazda and his aides, the Holy Immortals, who reveal to him the "Good Religion." Harassed by his opponents, he flees to eastern Iran, where he converts the Kianid king, Vishtaspa, to his religion. He marries the daughter of Vishtaspa's good vizier, Frashaoshtra, and gives his own daughter in marriage to Jamaspa, another good vizier of the King. A series of battles against the neighboring infidel tribes follows King Vishtaspa's conversion, and Zoroaster is killed at an altar during one of these battles.
Agathius (6th century A.D.) was already facing the difficulty of determining the time of Zoroaster when he observed that the Persians said that Zoroaster lived under Hystaspes (Vishtaspa), but that it was not clear whether they meant Darius's father or another Hystaspes. This question has continued into our own day. Whereas Samuel Nyberg placed Zoroaster in a remote period and among primitive people, Ernst Herzfeld (1947) insisted that he was related to the house of the Median kings and that his protector, Vishtaspa, was none other than Darius's father. However, one must follow the convincing argument of W. B. Henning (1951), who upholds the authenticity of the Zoroastrian tradition and places Zoroaster in the court of a king of eastern Iran whose domain was eventually absorbed into the Achaemenid empire. This makes Zoroaster a contemporary of Buddha and Confucius.
As to the native land of the prophet, all the evidence in the Avesta, including geographical names, points to eastern Iran as the scene of Zoroaster's activities. It is most probable that his alleged Median origin was a fabrication of the Magi.
The Zoroastrian religion has gone through different phases, attracting in the course of time many elements from different sources. Among these sources are the pre-Zoroastrian religion of the Iranians and the ritualistic cult of the Magi, but the central element remains the message of Zoroaster himself. It was this message which shaped the new religion and afforded the Iranians spiritual comfort and cohesion for many centuries.
The most characteristic aspect of Zoroaster's faith is belief in dualism. He conceived of two primeval powers active in the universe, Good and Evil. Our world is the scene of their conflict and admixture. The outcome of this conflict, upon which depends the destiny of man, is decided as much by man's choice as by any other factor. The choice is between siding with Ahura Mazda and following the path of truth, or uniting with Angra Mainyu (Ahriman) and following the way of falsehood. In the fateful struggle between Ahura Mazda and Angra Mainyu, it is man and his deeds which hold the balance. It is through the good thoughts, good words, and good deeds of pious men and women that the forces of Good eventually triumph. There will be a day of reckoning when those who have resisted the temptations of Angra Mainyu and have followed the dictates of the "Good Religion" will be blessed.
In assigning this choice to man, Zoroaster raises him to an exalted rank in the scheme of creation. Man's noble position and his positive contribution to the triumph of righteousness is the second important characteristic of Zoroaster's message. His religion is not affected by a notion of original sin or by ascetic tendencies. The raising of children and the planting of trees are stressed as meritorious deeds. Zoroaster's kingdom of God is not necessarily a vision to be realized only in the hereafter.
Zoroaster, who seems to have reacted against a form of monotheism, reveals a striking and original way of thinking. From the Gathas we gain the impression of an impassioned preacher who strives for the material and spiritual well-being of his people. The success of his faith bears witness to the pertinence of his message for his people.
An English translation of the Gathas is in Jacques Duchesne-Guillemin, The Hymns of Zarathustra, translated from the French by M. Henning (1925), and of the Avesta in The Zend Avesta, translated by James Darmstetter (2d ed. 1895). A. V. Williams Jackson, Zoroaster: The Prophet of Ancient Iran (1899), is still the most comprehensive work on the life of Zoroaster. Also useful is Ernst Herzfeld, Zoroaster and His World (2 vols., 1947). For a discussion and critique of various opinions on Zoroaster's time and place, the best source is W. B. Henning, Zoroaster (1951). A general discussion of Zoroastrianism is Robert C. Zaehner, The Dawn and Twilight of Zoroastrianism (1961), which contains useful bibliographies.