Zarathustra (Disputed Dates)

The Gathas, the only voice directly attributable to Zarathustra

The Mazdean scriptural corpus, the Avesta, originally contained, according to Sassanid tradition, twenty-one books (nasks), of which only a fraction has reached us: most were lost or destroyed after Alexander the Great’s invasion, then during the ensuing turmoil, before a major restoration and codification were undertaken under the Sassanid dynasty (224–651)^[5]. The text we possess today is divided into five major sections: the Yasna (which includes the Gathas), the Visperad, the Yashts, minor texts, and the Vendidad^[6].

Within this corpus, only one textual layer is directly attributed to Zarathustra himself: the Gathas, seventeen hymns divided into five sections, inserted at the heart of the Yasna (chapters 28 to 53)^[7]. Composed in an archaic dialect distinct from the rest of the Avesta, Old Avestan (or Gathic), these hymns are considered by tradition as “holy psalms, chants that have preserved the metrical sayings of Zoroaster himself,” used in his preaching^[8]. No other source, neither in the later Avesta nor in the much later Pahlavi (Middle Persian) tradition, can claim comparable proximity to the prophet’s voice.

It is precisely this rarity that makes dating so difficult. The German philologist Hermann Lommel (1885–1968), one of the greatest Avestan specialists of the 20th century, already summarized the state of the question in 1930 with a phrase that has become famous:

“When and where Zarathustra lived, we do not know.”
— Hermann Lommel (1930), cited in Encyclopaedia Iranica, art. “Zoroaster ii. General Survey”^[9]

Nearly a century of additional philological and archaeological research has not fundamentally overturned this conclusion: there still exists, in the words of contemporary specialists, neither a definitive consensus on the date nor on the place, and some researchers even question Zarathustra’s historicity or his status as the true author of the Gathas^[10].

The debate on the author: Kellens, Pirart, and the question of the third person

A further, more recent complication deserves honest mention. The French Avestan scholars Jean Kellens and Éric Pirart argued from the 1980s onward that the prophet’s name appears ten times in the Gathas in the third person — a fact which, according to them, makes the hypothesis of a single author referring to himself in the third person “perfectly improbable,” notably in the passage Yasna 46,14, where Zarathustra seems to question his own mission as if speaking of another^[11]. For Kellens, the Gathas would thus be less the work of an individual than “the emanation of a mentality,” that of a priestly guild organized around the fire cult^[12].

This thesis remains a minority view: the dominant scholarly tradition, supported by Vedic parallels — where poets address themselves in the third person according to a well-attested poetic convention — continues to defend individual authorship of the Gathas, holding their tone of personal and passionate inspiration incompatible with a simple anonymous collective production^[13]. The vast majority of current specialists, including those cautious about dating, therefore continue to treat Zarathustra as a real historical individual, author at least of the core of the Gathas.

The Silence of Herodotus and Classical Greek Historians

One fact deserves emphasis for the rigor of the investigation: Herodotus, who completed his Histories around 440 BC and devotes a detailed section to Persian religion — the absence of statues and temples, sacrifices on heights, the worship of the sun, moon, earth, fire, water, and winds^[14] — never mentions Zarathustra by name. It is later authors — Xanthus of Lydia, then Ctesias, Aristotle, Eudoxus of Cnidus, Hermippus, Plutarch, Diogenes Laërtius, and finally Agathias, much later, in the 6th century AD — who, each in their own way, report the name and attempt to date the Persian prophet^[15]. This Herodotean silence does not prove the nonexistence of Zarathustra in Herodotus’s time, but it illustrates, once again, how the figure of the prophet remains shrouded in documentary uncertainty from the earliest sources that approach Persian religion from the outside.

The Late Mazdean Dating: “258 Years Before Alexander”

The Zoroastrian tradition itself eventually assigned a precise date, but late and through retrospective reasoning. The Bundahishn, a major cosmogonic treatise in Middle Persian compiled in the 8th-9th centuries AD — more than a thousand years after the events it claims to date — places the “Age of Zoroaster” 258 years before Alexander^[16]. This date results from a purely calculative operation: after the Seleucid conquest, which imposed a new calendar era, the “Era of Alexander,” the Mazdean clergy sought to establish in return an “Era of Zoroaster” by counting back, generation by generation, to an estimated date for the prophet’s life^[17]. The resulting figure corresponds, depending on the interpretation of the reference point, to a date between 660 and 583 BC^[18], the number “258” not necessarily indicating his birth but one of three major events in his life: his vision received at thirty years old, the start of his preaching at forty, or the conversion of King Vishtaspa two years later^[19].

Iranologist A. Shapur Shahbazi, in his authoritative study on the subject, demonstrated how this figure, far from being a reliable historical memory, results from a counting artifact specific to the Seleucid period^[20]. The scholarly debate on the reliability of this “traditional” date goes back at least to the 19th century: scholars such as Windischmann, Tiele, and Geiger had already judged the date insufficiently founded and proposed pushing Zarathustra back to around 1000 BC, while other 20th-century scholars, notably Walter Bruno Henning (1908-1967), defended the plausibility of the late dating^[21]. The Italian Iranologist Gherardo Gnoli (1937-2012), after exchanges with Ilya Gershevitch, himself came to accept the likelihood of this traditional date, relying notably on the late testimony of the Byzantine historian Agathias (6th century AD), who nonetheless acknowledged the uncertainty of the problem:

“It is not possible to fix precisely the dates of his floruit [...] The Persians simply say that he lived in the time of Hystaspes, without specifying whether they mean the father of Darius or some other monarch of the same name.” — Agathias, Histories, 6th century AD, cited and commented on by Gherardo Gnoli, “Agathias and the Date of Zoroaster,” in Eran ud Aneran: Studies Presented to Boris Ilich Marshak, Venice, 2003^[22]

Greek Fantasies: From Five Thousand to Six Thousand Years Before Plato

Opposite this “low” dating, the earliest Greek sources attribute to Zarathustra a truly staggering antiquity. Xanthus of Lydia, a 5th-century BC historian, was the first known Greek author to mention Zarathustra by name^[23]. According to Diogenes Laërtius (3rd century AD), who reports these traditions in the prologue to his Lives of the Philosophers, the Platonist Hermodore placed the beginning of the era of the magi, starting with Zoroaster the Persian, five thousand years before the Trojan War, while the same Xanthus of Lydia counted six thousand years between Zoroaster and Xerxes’ expedition^[24]. The Latin naturalist Pliny the Elder (23-79 AD), citing Eudoxus of Cnidus and Aristotle, similarly reports that Zoroaster lived six thousand years before Plato’s death^[25], while Plutarch (c. 46-125 AD), in his treatise On Isis and Osiris, adopts a comparable chronology:

“Zoroaster the Mage, who lived, according to tradition, five thousand years before the siege of Troy.” — Plutarch, De Iside et Osiride, 1st-2nd century AD^[26]

These astonishing figures — up to six thousand years, while humanity itself did not exist according to traditional biblical chronology at such a remote date — should not be read as historical data but as symptoms of a well-identified phenomenon by specialists: in the Hellenistic world, Zoroaster became a legendary figure associated with primordial Eastern wisdom and increasingly with magic. Pliny explicitly ranks him among the “inventors of magic”^[27], and entire treatises on astrology were soon attributed to his name: the historian Hermippus (3rd-2nd century BC) claimed to have edited commentaries on “Zoroastrian” works totaling two million verses, spread over about eight hundred papyrus scrolls^[28] — an obviously fictitious production, since no original of this magnitude ever existed nor could materially exist at the claimed time. Most of this magical pseudepigraphic literature was in fact attributed not to Zoroaster but to a distinct figure, Ostanes, another legendary mage associated with the Persian court^[29].

Modern Linguistic Dating: Around 1500-1000 BC

Since the 19th century, the dominant method for dating Zarathustra no longer relies on late Mazdean traditions or Greek fantasies but on the internal linguistic analysis of the Gathas themselves. Old Avestan Gathic indeed shows striking parallels with Vedic Sanskrit of the Rigveda (composed around 1500-1100 BC): shared vocabulary, grammar, and poetic meters betray a common archaic Indo-Iranian origin^[30]. The Gathic word ahura, “divine lord,” is precisely identical to the Vedic word asura^[31] — proof of a very ancient linguistic kinship between the two religious traditions, Iranian and Indian, stemming from a shared cultural background of the Bronze Age. It is on this basis that the British historian Mary Boyce (1920–2006), the foremost Western specialist on Zoroastrianism in the 20th century, proposed placing Zarathustra between 1700 and 1000 BCE, or more precisely between 1500 and 1000 BCE, considering that the two corpora, Gathic and Vedic, described comparable Bronze Age societies^[32]. Her comprehensive work, published in 1979, thus traces the continuous history of Mazdaism from the preaching of Zoroaster to the present day, over a total duration of about 3,500 years^[33] — which mechanically places the origin of the preaching around 1200 BCE.

However, this “early” dating has not ended the debate. The French linguist Jean Kellens, while aligning with the linguistic rather than traditional camp, noted in 2011 that “over the past ten years, a general consensus has gradually emerged in favor of dating the Gathas around 1000 BCE”^[34] — a date slightly later than Boyce’s, but still far from the “258 years before Alexander” of the late tradition. More recently, the linguist Almut Hintze, within research funded by the European Research Council, places Zarathustra’s life at about 3,500 years ago, i.e., during the course of the 2nd millennium BCE^[35].

The following table summarizes the main positions defended in the history of research:

Where Was Zarathustra Born? The Geographical Problem

The uncertainty surrounding Zarathustra’s date extends, almost identically, to his place of birth. Even the Greek sources diverge: the historian Ctesias places him in Bactria (north of present-day Afghanistan), while Diodorus Siculus locates him among the Ariaspes, a people established in the Sistan region (southeast of present-day Iran)^[36]. Contemporary specialists, lacking a definitive conclusion, tend to favor an origin in eastern Iran, rather than in the western regions (Media, proper Persia) where Mazdaism was later institutionalized under the Achaemenids^[37] — without a final agreement on whether to prioritize the northeast (Bactria, Chorasmia) or the southeast (Sistan) of this vast area.

What to Retain? A Fragile Consensus, Not a Certainty

Readers expecting a single, assured date for Zarathustra must accept a more modest but honest conclusion: there is currently no dating that commands unanimous agreement among specialists. The widest possible range extends from 1750 BCE (early linguistic dating) to 583 BCE (traditional late dating), a gap of over a thousand years^[38]. The most widespread consensus today, though not definitive, places his life around 1000 BCE, give or take a century or two^[39]. It is this persistent uncertainty, acknowledged even by the best specialists, that justifies treating the question of Zarathustra’s dates as a problem in its own right rather than as a mere biographical detail — hence the very title of this article.

A Family of Priest-Poets: the Spitāma

In the absence of independent contemporary sources, Zarathustra’s biography can only be reconstructed by cross-referencing the scattered indications within the Gathas themselves and the much later tradition of the recent Avesta and Pahlavi texts. According to this tradition, he belonged to the clan of the Spitāma: his father was named Pourushaspa and his mother Dughdova^[40] — names which, according to specialists, appear only in the later tradition (recent Avesta and Pahlavi books), not in the Gathas themselves. Pahlavi genealogy makes him the son of Pourushaspa, the grandson of Purtaraspa and the descendant, in the fourth generation, of an ancestor named Haechadaspa^[41].

The Gathas reveal a man facing strong hostility from the powerful of his time: he complains of being rejected by the karpans and the kawis — rival priests and local political leaders — and mentions his banishment from his own family and clan^[42]. This conflict with the religious and political establishment of his time is one of the few biographical elements that can be drawn directly from the oldest text, without relying on later legendary embellishments.

The Vision Received at Thirty

According to unanimous tradition, Zarathustra received, around the age of thirty, a revelation from Ahura Mazda conveyed through Vohu Manah (the “Good Spirit” or “Good Thought”), one of the great personified divine attributes of Mazdaism^[43]. It is this foundational experience which, according to the traditional account, launched him into public preaching — preaching which, at first, met only rejection and hostility from the established religious authorities.

Rejection, Exile, Then the Conversion of King Vishtaspa

After years of difficult preaching, Zarathustra is said to have obtained, around the age of forty-two, the decisive support of a king named Kawi Vishtaspa, whose kingdom is traditionally associated with Bactria, and of his wife, Queen Hutaosa^[44]. This royal conversion constitutes, in Mazdean tradition, the pivotal event that allowed Zarathustra’s message to become firmly established and transmitted to a court, thus to an institutional posterity — exactly as, in other religious traditions of Antiquity and the Middle Ages, the conversion of a sovereign ensures the survival of a preaching that, if private, would have died with its founder.

It should be noted, with the caution required by a serious encyclopedia, that this Kawi Vishtaspa has never been identified with certainty with a historically attested Persian figure: he should not be confused with Hystaspes, the father of the great Achaemenid king Darius I (r. 522–486 BCE), although the Byzantine historian Agathias himself noted this possible ambiguity in the Persian traditions he reported^[45].

Marriages, Children, and Death at Seventy-Seven Years

According to tradition, Zarathustra married three times. From his first two wives were born six children: three sons — Isat Vâstra, Urvatat Nara, and Hvare Chithra — and three daughters, including Pouruchista, who plays a notable role in the Gathas themselves^[46]. His third wife, Hvōvi, remained childless^[47]. Tradition also reports that he died at the age of seventy-seven years and forty days, killed in Balkh by a hostile priest during an attack led by an enemy people, the Turanians^[48].

Ahura Mazda, the "Lord of Wisdom"

All of Zarathustra’s theology revolves around a single supreme being, Ahura Mazda — literally the "Lord of Wisdom" or "Wise Lord." The article that the Catholic scholar Mgr Louis Charles Casartelli (1852–1925), Bishop of Salford and a recognized specialist in Avestan and Pahlavi, devoted to the subject in the Catholic Encyclopedia of 1913, describes him as "a pure spirit," endowed with eternity, wisdom, truth, goodness, majesty, and power, creator of all good creatures, "supreme Legislator, Rewarder of moral good and Punisher of moral evil"^[49]. This definition, formulated by a Catholic bishop himself trained in Iranian studies — his doctoral thesis, The Religious Philosophy of Mazdaism under the Sassanids, defended at Louvain, attests to this^[50] — demonstrates that Mazdean monotheism was very early recognized, including by Catholic scholars, as a theological construction of remarkable rigor for its time and cultural context.

The Two Twin Spirits: Spenta Mainyu and Angra Mainyu

The most characteristic feature of Zoroastrian theology, the one that most clearly distinguishes it from biblical monotheisms, is the dualism of the two Spirits, presented in one of the most commented passages of the Gathas, Yasna 30, 3. The American Sanskritist and Avestan scholar Stanley Insler, in his authoritative edition of the Gathas, offers the following translation:

"Yes, there are two fundamental spirits, twins, reputed to be in conflict. In thought and in word, in deed, they are two: the good and the evil." — Yasna 30, 3, French translation based on Stanley Insler, The Gathas of Zarathustra, Acta Iranica 8, Leiden, Brill, 1975^[51]

These two twin spirits are Spenta Mainyu (the "Beneficent Spirit" or "Holy Spirit"), through whom Ahura Mazda conceives and governs creation, and Angra Mainyu (the "Destructive Spirit"), source of evil, falsehood, and death^[52]. According to the exposition given by Mgr Casartelli, Angra Mainyu is conceived as "existing entirely independently" of Ahura Mazda and "destined for destruction at the end of time"^[53], which entails, from the origin of the world, a state of "continuous war" between the two principles^[54]. A practical and unsettling consequence of this dualism, noted by Casartelli himself, is that "all dangerous, harmful, or poisonous animals and plants are evil by their very creation and nature" — a position that sharply contrasts with the Buddhist principle of non-violence (ahimsa) toward all animal life without distinction^[55].

The Amesha Spenta, Personified Divine Attributes

Around Ahura Mazda revolve six — or seven, if including Spenta Mainyu himself — great entities called Amesha Spenta ("Beneficent Immortals"), which Mgr Casartelli describes as "simply personified attributes of the Creator himself"^[56], but which become, in later tradition, "increasingly concrete characters or spirits"^[57]:

Other spirits intervene in this system, notably Mithra, originally a solar deity who became the "Spirit of Light and Truth," Sraosha ("Obedience"), and Rashnu ("Justice")^[58]. Opposed to them stand the demonic forces, the daevas and the druj (personified Lie), led by Aka Manah (the Evil Spirit) and including notably Aeshma, demon of wrath^[59] — a name which, through a remarkable linguistic transmission via Aramaic, eventually gave rise to the demon Asmodeus of the biblical Book of Tobit.

Notably for the Catholic reader: later Pahlavi literature even identifies Vohu Manah as the "Son of the Creator," explicitly linking him to the Alexandrian Logos^[60] — a suggestive parallel, which Mazdean tradition itself developed well after contacts between the Iranian world and the Hellenistic and Christian worlds, and which should therefore be treated as a late convergence rather than a source of Christianity.

The Ethical Triad: Good Thoughts, Good Words, Good Deeds

Zoroastrian morality is traditionally summed up in a three-part formula, which remains the most popular summary of Mazdaism to this day: Humata, Hukhta, Hvarshta — "good thoughts, good words, good deeds." Mgr Casartelli emphasizes that this ethics rests on free will: man, capable of choosing between Ahura Mazda and Angra Mainyu, thereby distinguishes himself from the fatalism of certain Indian traditions, in a system of "essential optimism: if there is human sin, there is also repentance and atonement"^[61]. The moral teaching especially condemns "heresy, lying, perjury, sexual sins, violence, tyranny," and confers religious value even on agriculture itself, the Zoroastrian reform being, in Casartelli’s words, "as much social as religious"^[62]. The article nevertheless acknowledges a trait it calls "repugnant": the glorification, in some late texts, of marriage between close relatives (khvaetvadatha), a practice that modern Parsis have since rejected^[63].

The Chinvat Bridge and the Judgment of the Soul

After death, according to Mazdean doctrine, the soul remains near the body for three days before presenting itself at the Chinvat Bridge ("bridge of discernment"), where it is judged by Mithra, Sraosha, and Rashnu^[64]. The appearance of the bridge varies according to the life led by the deceased: for the just soul, it widens and becomes easily passable, while a spirit named Daena, personification of the soul’s own religious conscience, comes to meet it in a beautiful and luminous form; for the wicked soul, the bridge narrows to the edge of a blade, and the demon Vizaresh drags the sinner into the house of Lies^[65]. The righteous then enter "heaven (Auhu vahishta, the Garo nmana or 'House of Song')," while the wicked fall into hell^[66]; an intermediate state, the Hamestakan, receives souls whose good and bad deeds exactly balance, neither suffering nor happy^[67].

The End of Times: Frashokereti and the Saoshyant

Individual judgment at the Chinvat Bridge does not exhaust Mazdean eschatology, which reserves its broadest vision for the end of cosmic time: the Frashokereti, or "Final Renovation," the moment when evil will be definitively destroyed and all creation will regain perfect unity with Ahura Mazda^[68]. This event is to be inaugurated by the Saoshyant ("He who brings benefit"), an awaited savior figure, descendant of Zarathustra himself and, according to tradition, miraculously born of a virgin from the prophet’s seed preserved in a lake^[69]. The Saoshyant is to lead the resurrection of the dead, the final judgment, and the ultimate battle between the forces of good and evil, before the old world fades away to make room for eternal and reunified bliss^[70]. Mgr Casartelli’s article explicitly notes that this description — Resurrection, General Judgment, apokatastasis or renewal of the entire world by a great conflagration — offers striking parallels with Christian apocalyptic imagery^[71].

Darius and the Achaemenid Kings, the First Attested "Worshippers of Mazda"

While Zarathustra’s life eludes any secure chronology, the history of Mazdeism as the state religion of ancient Persia is well documented from the great royal Achaemenid inscriptions. King Darius I (r. 522–486 BCE) presents himself in his inscriptions as a fervent "worshipper of Mazda," explicitly invoking Ahura Mazda as the source of his royal legitimacy^[72] — making him the first Persian ruler whose Mazdean devotion is directly attested by contemporary sources rather than retrospective tradition. From then on, this religion became, for most of the Achaemenid period (550–330 BCE), the official faith of the vast Persian empire, from the Aegean to the Indus.

Zurvanism, the Heresy That Sought to Unify Dualism

From the Parthian period and especially under the Sassanids, a heterodox current developed within Mazdeism: Zurvanism, which makes Zurvan — Infinite Time — a primary principle preceding Ahura Mazda and Angra Mainyu, engendering the two spirits as equal and opposite twins^[74]. This doctrine, by subordinating Ahura Mazda himself to a higher principle and weakening human free will in favor of a form of temporal fatalism, was condemned as heresy by later Mazdean orthodoxy: the Denkard, a 9th-century Pahlavi compilation, explicitly calls it a doctrine "of demonic inspiration"^[75]. Nevertheless, Zurvanism enjoyed wide diffusion under the Sassanids before declining with the empire’s fall^[76].

The Catastrophe of Alexander and the Sassanid Reconstruction of the Avesta

Mazdean tradition itself attributes to the conquest of Alexander the Great (330 BCE) the loss of most of the original scriptural corpus — an episode that explains, in its own eyes, why the Avesta that has come down to us is only a fragmentary remnant of the original twenty-one books^[77]. It was only under the Sassanid dynasty (224–651), notably during the reign of Shapur II (309–379), that a systematic effort to restore and codify the text was undertaken^[78] — a reconstruction work which, precisely because it took place several centuries after Zarathustra’s own life, partly explains why the latest layers of the Avesta and the accompanying Pahlavi literature cannot be treated as direct witnesses of his original preaching.

The Parsis, Heirs of Mazdeism after the Arab Conquest

The Arab-Muslim conquest of Persia, completed in 651, ended Mazdeism’s status as state religion and led to a gradual demographic decline on Iranian soil itself^[79]. Some Persian Zoroastrians then chose exile rather than forced conversion, settling in the Gujarat region of India: their descendants, the Parsis, still form today, mainly in Bombay, a prosperous community of several tens of thousands of faithful^[80]. About 10,000 Zoroastrians also remain in Iran itself, scattered throughout the country^[81].

An Eastern Master of Wisdom for Greek Philosophers

For many Greek authors, from the classical period onward, Zoroaster became the emblematic figure of an Eastern wisdom that was both ancient and superior to Greek philosophy itself. Diogenes Laërtius, in the prologue to his Lives of the Philosophers, speaks favorably of the Persian magi and even proposes a fanciful Greek etymology of his name, deriving it from astrothútēs, “one who sacrifices to the stars”^[82]. Several ancient authors — Polyhistor, Apuleius, and even the Christian Clement of Alexandria, citing older sources — went so far as to claim that Pythagoras was a disciple of Zoroaster^[83], a legend without serious historical foundation but revealing the immense prestige the Persian prophet’s name enjoyed in the Greco-Roman philosophical imagination.

Zoroaster as the “Inventor of Magic”: The Hellenistic Legend

However, this reverence for Eastern wisdom shifted during the Hellenistic period toward a very different figure: that of the primordial magician. Pliny the Elder explicitly calls Zoroaster the “inventor of magic” in his Natural History^[84], and it was under his name that countless pseudepigraphal treatises on astrology and occult sciences circulated throughout the Greco-Roman world — most of which, as we have seen, were actually attributed to the related figure of Ostanes^[85]. This legend of Zoroaster the magician, largely disconnected from the true theology of the Gathas, enjoyed lasting popularity in Western esoteric literature up to the Renaissance and beyond — a legacy that must be clearly distinguished, for historical accuracy, from the authentic doctrine of Mazdaism as transmitted by the Gathas and the Avesta.

The Christian Legend of the Magi of Bethlehem and the “Prophecy of Zoroaster”

One point deserves special attention for a Catholic reader: certain ancient and medieval Christian traditions associated the Magi who came to worship the Infant Jesus (Mt 2:1-12) with Zoroastrian priests, even attributing to them knowledge of a prophecy dating back to Zoroaster himself, foretelling the appearance of a star signaling the birth of a divine king. The Syriac apocryphon called the Revelation of the Magi, preserved in the 8th-century Chronicle of Zuqnin, presents the magi as descendants of Seth, guardians of an ancient prophecy announcing that “a star of indescribable brilliance would one day appear, announcing the birth of God in human form”^[86]. Another apocryphal text, the Arabic Gospel of the Infancy, explicitly states that the magi were following a prophecy of “their prophet Zoradascht,” that is, Zoroaster^[87].

Here it is important to carefully distinguish, with the rigor required by a serious Catholic encyclopedia, what the canonical Gospel of Matthew reports — magi coming from the East, without further specification of their exact religious origin, guided by a star they interpret according to their own knowledge — and the later apocryphal elaborations, Syriac and Arabic, which seek to fill this silence by linking their knowledge to an explicit Zoroastrian prophecy. These apocryphal accounts, composed several centuries after the events in Syriac Christian milieus closely connected with the Iranian world, cannot be considered direct historical testimony about Zarathustra’s own thought; rather, they illustrate how early Christian tradition sought to integrate, within the mystery of the Epiphany, the conviction that God had prepared, even among the most distant pagan nations, “seeds” of messianic expectation — a conviction that the Catholic magisterium would much later articulate precisely in the doctrine of the semina Verbi^[88].

Nietzsche and His Inverted Zarathustra

Finally, it should be noted, for completeness, that the very name Zarathustra gained a literary and philosophical fortune in the 19th century entirely detached from historical Mazdaism: the German philosopher Friedrich Nietzsche made him, in Thus Spoke Zarathustra (1883-1885), the mouthpiece of his own thought. Nietzsche himself explains, in his autobiography Ecce Homo (1888), why he chose this particular name:

“Zarathustra created this error, the most fatal of all, which is morality: therefore he must also be the first to recognize it [...] The fact that Zarathustra is more truthful than any other thinker does not exclude, but rather implies, that he is the exact opposite of a moralist.” — Friedrich Nietzsche, Ecce Homo, 1888, chapter “Thus Spoke Zarathustra,” § 3^[89]

Nietzsche deliberately prefers the ancient Persian form “Zarathustra” to the Hellenized French form “Zoroaster,” paying homage to the Iranian prophet as the first great founder of a morality based on the distinction between good and evil, before making the eponymous character of his own book the literary instrument of a complete reversal of that very morality^[90]. This philosophical appropriation, largely independent of the actual content of the Iranian prophet’s preaching, must obviously not be confused with the historical Mazdaism presented in this article.

What a Zoroastrian Bishop Recognized as True

It would be mistaken to believe that the esteem shown by a Catholic toward Mazdaism is a post-conciliar novelty. As early as 1913, the Bishop of Salford, Mgr Louis Charles Casartelli (1852–1925), author of a notable doctoral thesis on The Religious Philosophy of Mazdaism under the Sassanids and editor of the articles devoted to the Avesta in the Catholic Encyclopedia, reported the judgment of a Jesuit confrere, Father Ernest Hull:

“The highest religious achievement to which human reason, without the aid of revelation, can attain.” — Fr. Ernest Hull, S.J., cited by Mgr Louis Charles Casartelli, “Theological Aspects of Avesta,” The Catholic Encyclopedia, vol. 2, New York, Robert Appleton Company, 1913, quoting the Bombay Examiner of March 28, 1903^[91]

Casartelli himself summarizes the Zoroastrian theological system as a “monotheism modified by a physical and moral dualism, with an ethical system based on a divinely revealed moral code and human free will”^[92]. Thus, a Catholic scholar, recognized expert in the field, could already at the beginning of the 20th century recognize in Mazdaism an authentic effort of human reason to approach, without the aid of biblical revelation, divine unity, moral demand, and eschatological hope — a judgment that anticipates, several decades before Vatican II, the principle the council would formulate for all major non-Christian religious traditions:

“The Catholic Church rejects nothing that is true and holy in these religions. She regards with sincere respect those ways of acting and living, those rules and doctrines which, although differing in many respects from what she herself holds and proposes, nonetheless often reflect a ray of that truth which enlightens all men.” — Second Vatican Council, declaration Nostra Aetate, October 28, 1965, § 2^[93]

The Question of Dualism and the Problem of Evil

The most original—and from the Catholic faith’s point of view, the most problematic—feature of Zarathustra’s doctrine remains its dualism: two principles, one good, the other evil, opposing each other since the origin of the world. This appealing solution to the problem of evil—God is not responsible for evil since evil has its own independent and co-eternal source—has had considerable influence, notably through Manichaeism, a system founded in the 3rd century by the Babylonian prophet Mani, which adopts and radicalizes Mazdean dualism by associating it with Christian and Buddhist elements, and which captivated, for nearly nine years, a young African rhetorician named Augustine of Hippo before his conversion^[94]. A detailed doctrinal analysis of this dualistic solution to the problem of evil—its apparent strength, its logical dead ends, and the Catholic response based on evil as privation rather than substance—has already been developed in the Ignispedia article dedicated to this subject, to which the reader wishing to deepen this specific question is referred^[95].

It suffices here to recall the decisive point: Mazdean dualism, by making evil an eternal and uncreated principle, encounters a difficulty that biblical monotheism avoids from the outset. If Angra Mainyu exists from all eternity, independently of Ahura Mazda, then Ahura Mazda is no longer truly the unique and absolute Creator of all things; his sovereignty is, in fact, limited by a rival he did not create and whom he cannot, logically speaking, destroy without contradicting himself within his own system^[96]. Catholic faith, on the contrary, holds moral evil to be a privation of due good, not a substance or positive power rivaling God— a position that allows affirming without contradiction the omnipotence and absolute goodness of a unique God, while giving rightful place to created freedom as the real origin of sin.

The Hypothesis of an Influence on Post-Exilic Judaism: An Honest Debate

An academic question deserves to be presented with all the honesty this encyclopedia requires: several historians of religion, foremost among them Mary Boyce, have argued that the Jews’ stay under Persian administration—from the capture of Babylon by Cyrus in 539 BC until Alexander’s conquest in 332 BC—exerted a decisive influence on the development, in post-exilic Judaism, of doctrines such as the resurrection of the dead, a personified cosmic adversary (Satan), named angelology and demonology, and a final eschatological judgment—many themes that find striking parallels in Mazdean theology of Ahura Mazda against Angra Mainyu and the Saoshyant^[97].

This thesis, however, calls for several serious reservations, which American historian Edwin M. Yamauchi detailed in his reference study Persia and the Bible. The most decisive problem is chronological: the Mazdean texts presenting the most developed version of resurrection, final judgment, and the Saoshyant born of a virgin—the Bundahishn and the Zand-i Wahman Yasn—are only attested, in their current form, from the 8th–10th centuries after Jesus Christ, well after Christianity itself had spread in the Iranian sphere^[98]. To claim that post-exilic Judaism of the 5th or 4th century BC “borrowed” from a Mazdean doctrine whose closest formulation to biblical texts is attested only a thousand years later therefore presupposes, at minimum, the hypothetical existence of Mazdean oral traditions far earlier than their first known written record—an unverifiable hypothesis that reverses, or at least seriously weakens, the very meaning of the argument.

Yamauchi also notes substantial doctrinal differences, not mere nuances, between the two conceptions of resurrection: “Jewish dead, who are buried, rise from the dust of the earth, whereas Persian dead, who are exposed [to vultures, according to the Mazdean rite of corpse exposure], must be recreated from the elements. In Zoroastrianism, resurrection is linked to the trial by fire and renewal, while in Judaism, the hope of resurrection means life beyond the grave with Yahweh”^[99]. Protestant theologian Walther Eichrodt, in his classic study of Old Testament theology, already concluded that the idea of Persian influence on the eschatological hope of resurrection attested in the Old Testament “does not withstand a reasonably detailed comparison”^[100]. Other specialists, such as Second Temple Judaism historian Lester Grabbe, while not excluding some degree of diffuse Persian influence on Jewish apocalyptic vocabulary or imagery, emphasize that the specificity of Jewish monotheism and its own theology of the Covenant cannot be reduced to a mere copy of external borrowings^[101]. A Catholic therefore has no reason to yield to the concern that this hypothesis might provoke. On the one hand, it remains an open scholarly debate, not a demonstrated conclusion: the chronology of the Mazdean texts themselves makes the hypothesis of a direct borrowing fragile rather than obvious. On the other hand, and above all, the Catholic doctrine of Progressive Revelation does not need to deny any cultural contact between Israel and the surrounding nations to affirm that the deposit of biblical faith fundamentally proceeds from the action of God who “at many times and in many ways spoke in time past to the fathers by the prophets” (Heb 1:1)—a divine action that does not exclude that God used, as a providential cultural framework, the contacts between Israel and Persia to refine the vocabulary by which His people expressed truths already contained, at least in seed form, in a revelation prior to the exile.

What irreducibly separates them

The genuine esteem a Catholic can have for the moral rigor and theological depth of Mazdeism does not exempt one from clearly naming what decisively separates revealed faith from it.

A dualism versus a Trinitarian monotheism

The God of Zarathustra, as exalted as His conception may be, remains structurally opposed by a co-originating cosmic rival. The Christian God, on the other hand, is one and triune, without rival or competitor of any kind; evil is never a second creative power, but the privation of a due good, born of the freedom of creatures—fallen angels and men—and not of an eternal principle. The Catechism of the Catholic Church recalls that moral evil entered the world through the sin of free creatures, “incommensurably graver than physical evil” (§ 311), and that sin is “an offense against God,” “disobedience” and “a revolt against God” (§§ 1849-1850)^[102].

Multiple mediators, or the unique Savior born of a virgin

Mazdeism awaits a Saoshyant, an eschatological savior miraculously born of a virgin from the preserved seed of Zarathustra—a future figure, not yet come, biologically linked to the prophet’s lineage. Christian faith, however, confesses a salvation already accomplished once and for all in the person of Christ, “born of the Virgin Mary” (Apostles’ Creed), not by deferred seminal transmission but by the direct action of the Holy Spirit (Lk 1:35), and professes that “there is one God, and one mediator also between God and men, the man Christ Jesus” (1 Tim 2:5)—not a figure yet to come at the end of a cosmic cycle, but a Savior already come, dead and risen.

The entire creation declared good, not divided between two creators

Finally, where Mazdeism classifies certain animals and plants among creatures evil by nature because they are linked to Angra Mainyu^[103], biblical faith proclaims from Genesis that “God saw all that He had made, and behold, it was very good” (Gen 1:31)—all creation proceeding from a single good Creator, without exception or reservation, including those aspects that fallen man perceives as threatening or hostile.

Zarathustra remains an impressive figure for his coherence and the breadth of his legacy: a prophet whose date and place of birth are unknown within a millennium, but whose moral monotheism, ethical triad, and hope for a final judgment shaped, for over a thousand years, the religious life of the greatest empire of the ancient Near East, before leaving lasting—controversial but real—traces in the apocalyptic imagination of the ancient world and even in the Christian legend of the Magi of Bethlehem.

But where Zarathustra proclaims a unique God perpetually opposed by a co-eternal rival, and awaits a savior who must still be born of a virgin at the end of the ages, the Christian receives in Christ a hope already fulfilled: not two principles at war from the beginning, but one unique, sovereignly good God, whose evil is never more than a privation permitted out of love for created freedom; not a Saoshyant to come begotten by biological transmission, but a Savior already born, already dead, already risen, “the firstborn from the dead” (Col 1:18), who definitively conquered on the cross the destructive spirit that Zarathustra could only announce as to be defeated at the end of time.

• Mgr Louis Charles Casartelli, “Theological Aspects of Avesta” and “The Avesta,” The Catholic Encyclopedia, vol. 2, New York, Robert Appleton Company, 1913 — the reference Catholic exposition, by a bishop recognized as a specialist in Avestan and Pahlavi.
• Mary Boyce, Zoroastrians: Their Religious Beliefs and Practices, London, Routledge & Kegan Paul, 1979 — the reference synthesis on the continuous history of Mazdeism, with the linguistic dating of Zarathustra.
• A. Shapur Shahbazi, “The ‘Traditional Date of Zoroaster’ Explained,” Bulletin of the School of Oriental and African Studies, vol. 40, no. 1, 1977 — the reference study on the origin of the figure “258 years before Alexander.”
• Edwin M. Yamauchi, Persia and the Bible, Grand Rapids, Baker Book House, 1990 — the most rigorous critical examination of the hypothesis of Zoroastrian influence on post-exilic Judaism.
• Second Vatican Council, declaration Nostra Aetate (1965) and decree Ad Gentes (1965) — the magisterial framework for the Catholic view on non-Christian religions.
• On dualism as a response to the problem of evil, see the Ignispedia article Multiple gods?.