The Persian Encounter, or: the Indo-Iranian Substrate Present in Semitic Mythemes

1. The cosmic war everyone pictures

Open the imagination of almost anyone raised within reach of the Christian West, believer or atheist, churchgoer or lapsed, and you will find the same furniture already installed. There are two sides. There is a war between them, and the war runs the length of history. There is an adversary, a dark power with a will and a kingdom, opposed to the good. There is an end coming that will resolve the war, a judgement that will sort the living and the dead, and a world made new on the far side of the resolution. The shape is so familiar that it has leaked entirely free of religion: the secular apocalypses of climate collapse and runaway machines borrow it wholesale, two sides and a deadline and a reckoning, because it is the only shape for an ending that our culture knows how to think with.

The believer will tell you this picture comes from the Bible. The atheist, sneering at the believer, will agree with her about where it comes from and disagree only about whether it is true. Both are wrong in the same interesting way, and the way they are wrong is the subject of this instalment.

Open the older strata of the Hebrew Bible and look for the picture. It is not there. The God of pre-exilic Israel is not at war with a rival, because He has no rival; He is alone, and he is answerable for everything, the good and the ill alike, with nothing standing over against him. The figure later tradition reads as Satan is, in Job and in Zechariah, ha-satan, the accuser, a functionary of the divine court doing an assigned job, something between a prosecutor and an internal-affairs investigator, and he reports for work in heaven like everyone else. Death is Sheol, the neutral grave where all descend and none burn, not a battlefield and not a prize. There is no resurrection of the individual dead worth the name, no last judgement that sorts souls, no history divided into ages and bending toward a telos. The whole apparatus is simply absent, and then, across the few centuries that straddle the Babylonian exile, it arrives, more or less all at once, and installs itself so thoroughly that three thousand years later an unbeliever who has never opened Daniel can still sketch it from memory.

Attend to the strangeness of this, because it sets up the question that will run through everything below. The picture is dualist in its bones: two powers, light and darkness, locked in a struggle that organises all of history. And yet the tradition that came to carry it was, and insisted on remaining, fiercely monotheist: one God, and no other, and no second power beside him. How does a strict monotheism come to carry a dualist cosmology in its luggage? The short answer is that it met one, on the long road home from Babylon, and the meeting forced a question that the three great monotheisms of the West would each go on to answer in their own and incompatible ways. That question, and those three answers, are this post.

2. The hinge of the exile

The history is not in dispute, only its consequences. In 587 BCE the Babylonians took Jerusalem, burned the temple, and carried the kingdom's elite into exile. Fifty years later, in 539, Cyrus the Achaemenid took Babylon in his turn, and the following year issued the edict that permitted the exiles to return and rebuild. For the next two centuries the restored community of Yehud lived as a small province inside the Persian Empire, the largest the world had yet seen; Ezra and Nehemiah operated under Persian writ, the temple was rebuilt under Persian sponsorship, and the religious life that produced the canonical Hebrew Bible took shape under Persian administration. Whatever one wants to say about the mechanism of influence, the situation itself supplies it. These were not two cultures glimpsing one another across a frontier. One governed the other, intimately and for generations.

The texts register the encounter in a manner that ought to stop a careful reader cold. Second Isaiah, the exilic prophet of the return, calls Cyrus, a foreign king who did not worship the God of Israel and never would, māšîaḥ, the LORD's anointed, his messiah.¹ It is the only time the Hebrew Bible bestows that title on a gentile, and it is not a careless flourish; the prophet means that the Persian conqueror is the instrument of Israel's God, raised up by him for his purposes. The theology of the return is built around a Persian king. The contact could hardly be confessed more openly.

And then, a handful of verses later, in the same breath as the anointing of Cyrus, the prophet says something that reads, against the religious world he was living inside, like a deliberate and pointed refusal. I form light and create darkness, I make weal and create woe; I the LORD do all these things.² Set that sentence down in a culture that has just been introduced, by its imperial overlords, to a Wise Lord who is the author of light and good and a Hostile Spirit who is the author of darkness and evil, and the sentence stops being a piece of devotional boilerplate and becomes a thesis. The obvious thing to say, the thing the surrounding world was saying, is that light and darkness have separate authors, that good and evil are two principles at war. The prophet says no. One author. Both. The same hand makes the light and the dark, the weal and the woe, and there is no second power anywhere to share the work or the blame.

This is the hinge of the whole inheritance, and it is worth pausing on, because it tells us that the Judahites were not passive sponges. They knew exactly what they were being offered. They could see the shape of the dualism on the road, and in the very chapter that hands their salvation to a Persian king they drew a line through the one part of the Persian system that threatened the oneness of their God. What they did with the rest of the Persian system, the parts that did not threaten the oneness, is the rest of the story; but the line was drawn first, and it was drawn early, and it never moved.

3. What Zarathustra actually taught

To see what was on offer, we have to look at the religion of the empire, and here the difficulties begin, though I will defer most of them for one more section in order to lay the system out as its own tradition presents it.

Zarathustra, the prophet the Greeks called Zoroaster, is a figure of radically uncertain date; the proposals run from the second millennium to the sixth century BCE, and the honest scholar shrugs. His own compositions, the Gathas, survive embedded in the liturgical corpus called the Avesta, in an archaic Iranian dialect, and they are difficult, allusive hymns rather than a systematic theology. From them, and from the later tradition, the system can be assembled.

At its head stands Ahura Mazda, the Wise Lord, uncreated, supreme, and wholly good, the source of order and light and truth. Opposed to him is Angra Mainyu, later Ahriman, the Hostile or Destructive Spirit, the source of the lie and of death and of every corruption. The pivotal text is the thirtieth Yasna of the Gathas, which speaks of two primal spirits, the better and the bad, twins in some readings, who at the beginning made their choice between life and not-life, and between whom every conscious being must likewise choose.³ History is the bounded arena of their war, divided into great ages, and it is moving toward a resolution.

That resolution is the genuinely arresting part, because of what it so plainly resembles. At the end of the ages comes the frashokereti, the making-wonderful, the renovation in which the world is cleansed and perfected and the Hostile Spirit at last destroyed. The dead are raised, bodily; they cross the Chinvat bridge, the bridge of the separator, where their deeds are weighed, and the bridge broadens to an easy road beneath the feet of the righteous and narrows to a knife-edge beneath the wicked, who fall. A savior to come, the saoshyant, born in the last days of the prophet's own preserved seed, presides over the final renovation. A flood of molten metal pours across the world, and it is as warm milk to the saved and as agony to the damned, and when it has passed the world is healed and deathless and good, and evil is no more.

A reader who has spent any time at all in the eschatology of the Bible will by now be hearing a great many bells. The bells are real, and they are the reason this chapter of the river matters more than any we have traced so far. But before we draw the obvious conclusion, we have to walk straight into the problem that has made this the single most quarrelled-over question in the comparative study of religion, because to draw the conclusion without the problem is to commit, in reverse, the very error this entire series exists to expose.

4. The parallels laid side by side

First, though, the parallels, set out plainly, so that we know what is to be explained. The pattern is consistent and it is the same pattern every time: the feature is absent or marginal in pre-exilic Israel, and present and developed after the Persian encounter.

Take the adversary. Before the exile, ha-satan is the courtroom functionary of Job and Zechariah, a title with a definite article, the accuser, a member of the heavenly staff. By the Second Temple period, in the literature of the Scrolls and the apocalypses, he has hardened into Belial, into Mastema, into a Satan who is a cosmic enemy with a kingdom and an army, and the very grammar has shifted, from a title borne by a functionary to a proper name borne by a rival. The prosecutor has become the antagonist.

Take the angels. The faceless malʾakhim, the messengers, of the older texts give way, in Daniel and in Tobit, to named and ranked individuals, Michael and Gabriel and Raphael, an organised celestial hierarchy that did not exist before, mirrored below by an equally organised hierarchy of demons.

Take the dualism of light and darkness directly. The community at Qumran produced, in the Treatise of the Two Spirits, a text in which a Prince of Light contends against an Angel of Darkness, and the sons of light are arrayed against the sons of darkness, and the War Scroll choreographs their final eschatological battle.⁴ Set that beside the thirtieth Yasna and the resemblance is no longer a matter of mood; it is structural, and close enough to make a careful reader distinctly uneasy.

Take periodised history, the division of time into successive ages bending toward an end, as in Daniel's sequence of kingdoms. Take resurrection: Daniel 12:2, many of those who sleep in the dust of the earth shall awake, is the first unambiguous statement of individual bodily resurrection in the entire Hebrew Bible, and it is a second-century composition, late, well downstream of the Persian period, where before there had been only Sheol and silence.⁵ Take the renovated world, the new heavens and the new earth of the later prophets and the apocalypses.

Every one of these arrived in the same window. Each is thin or absent before the exile and substantial after the Persian centuries. One could, in principle, treat the convergence as coincidence, the independent flowering of a shared apocalyptic mood across the ancient Near East. One is permitted to bet that way. It is not the way to bet.

5. The landmine

And now the problem, which I am going to lean into rather than past, because the whole credibility of this series depends on refusing exactly the kind of confident overreach that the maximalist case here invites, and a reader who knows the field is by now drumming her fingers waiting to see whether I will be honest about it.

The problem is the sources, and it is severe. The Gathas are old, but they are cryptic hymns; they give us the two spirits and very little of the apparatus. The texts that lay out the full developed system, the eschatology of resurrection and renovation and the molten metal, the frashokereti in its elaborated form, are the Pahlavi books, the Bundahishn and the Denkard, and these are compilations of the ninth century of the common era.⁶ The ninth century. That is some fourteen hundred years after Cyrus stood in Babylon, and, far more awkwardly, it is centuries after the New Testament was written and contemporaneous with the early life of Islam. To lift the developed eschatology out of the Bundahishn and announce that the Jews borrowed it in 500 BCE is to read the destination back onto the source, to assume that what Zoroastrianism looked like under the Abbasid caliphs is what it looked like under the Achaemenid kings. It is precisely the sin this series spends its energy exposing in others, committed in the opposite direction, and it deserves no indulgence merely because the conclusion is one we find congenial.

James Barr made the case against the maximalists with real force in 1985, and it has not been answered so much as managed.⁷ We cannot, Barr observed, securely date most of the relevant Iranian material early enough to demonstrate that it was even available to be borrowed when the borrowing is supposed to have happened. The parallels, striking as they are, admit of other readings. They might run the other way: a Zoroastrian priesthood writing down its tradition under Muslim rule, surrounded by Jewish and Christian and Islamic eschatology, may itself have absorbed and systematised material that flowed toward it rather than from it, so that the ninth-century texts we are mining for the source are partly a record of the influence's return journey. Or the parallels might be independent developments, two traditions reaching similar apocalyptic conclusions from a shared regional mood without either handing anything to the other. None of these can be excluded, because the evidence that would exclude them does not survive.

The great maximalist, Mary Boyce, met this by arguing that Zoroastrian oral transmission was extraordinarily conservative, that the priesthood preserved its material with liturgical exactitude across the long centuries before it was committed to writing, and that the ninth-century books therefore faithfully transmit a system far older than its manuscripts.⁸ This is entirely plausible. It is also, in the particular, unprovable, which is exactly the trouble. We are asked to believe in the early existence of a developed doctrine on the strength of a conservatism we cannot independently verify for the doctrine in question.

So let me say the uncomfortable thing without softening it. The single most consequential claim available in this post, that the cosmic-dualist eschatology of the entire monotheistic West is Persian in origin, rests on a source base too late to nail down and a chain of transmission we cannot fully reconstruct. Anyone who tells you the Persian influence is proven is selling you something. And, in the interest of selling you nothing, I should add at once: so am I, if I turn around and tell you it has been refuted. It has not. What we have is a genuine and unresolved problem, and the responsible thing is to ask what survives it.

6. What we can responsibly say

A surprising amount survives it, once we stop demanding a proof the evidence cannot supply and ask instead what the balance of the evidence actually supports.

First, the negative datum stands entirely on its own, independent of any Iranian dating whatsoever. The apparatus, the developed Satan, the ranked angels, the cosmic dualism, the resurrection, the periodised eschatology, the renovated world, is demonstrably absent in pre-exilic Israelite religion and demonstrably present after the Persian period. That asymmetry is a fact about the Hebrew sources, not about the Pahlavi ones, and it requires an explanation whatever its ultimate source. Something happened across those centuries.

Second, the contact requires no special pleading. Two centuries of imperial rule is not a tenuous parallel in want of a transmission mechanism; the rule is the mechanism. Third, the direction of probable borrowing is not seriously in doubt. A small, recently shattered, recently deported subject people living inside the largest empire on earth does not, as a rule, export its cosmology to the imperial centre and leave the centre's own religion untouched. It imports. The arrow of cultural influence between a province and an empire points, overwhelmingly, one way.

But the fourth point is the decisive one, and it is the point at which the dating problem stops mattering as much as the maximalists' critics suppose, because it concerns not the donor but the recipient, whose texts we can date. Look at the shape of the Jewish inheritance. It is not the shape of coincidence, and it is not the shape of wholesale borrowing. It is, exactly and unmistakably, the shape of appropriation under constraint.

The Jews did not take the dualism whole. They took the war, the adversary, the angels, the resurrection, the judgement, the renovated world, the entire serviceable apparatus, and they declined the single element that mattered most to the system they took it from: the metaphysical independence of the evil power. In classical Zoroastrianism Angra Mainyu is uncreated, coequal with the Wise Lord, a genuine second principle standing at the origin of things. The Jewish Satan is never, at any point, that. He is a creature. He is a servant who went wrong, permitted, leashed, deployed, and finally answerable to the one God whose creation he is and whose authority he cannot escape. And standing guard over the whole transaction, drawn early and never erased, is the line from Second Isaiah: one hand forms the light and creates the darkness. Even in the Second Temple apocalyptic literature, the figure of the opposition (Mastema, Samayel, Semjaza, etc.) is always a created being and subordinate to El(ohim).

This is what it looks like when a monotheist culture meets a dualist one, finds the dualist furniture genuinely useful for problems its own theology had left painfully open, the problem of evil, the maddening delay of justice, the unbearable fate of the righteous dead, and imports the furniture while flatly refusing the foundation that came with it. The rabbis, centuries later, gave the refusal a name and made it a heresy: shtei reshuyot, two powers in heaven, the one thing a Jewish person must not say.⁹ The line that Isaiah drew became the wall the rabbis manned. And so Judaism's answer to the question the Persian encounter forced can be stated cleanly: absorb the cosmology, and guard the oneness. Take everything except the second God.

7. Christianity relaxes the oneness

Christianity inherited the whole of this apparatus, not from Persia directly but from the Second Temple Judaism in which it was born, and then it did two things that its parent tradition had specifically declined to do.

The first was a matter of degree. Christianity ran the cosmic war hotter than its sources required. Its Satan is grander than anything the rabbis would countenance, the god of this world in Paul's phrase, the ruler of this present age, a power with a real if doomed dominion. The Book of Revelation is, in its architecture, a cosmic battle of light against darkness in fully Christian costume, the dragon against the Lamb, the two assembled armies, the binding of the adversary, the lake of fire, and on the far side of it the new heaven and the new earth and the death of death. The dualist temperature, in other words, runs hotter in Christianity than in the Judaism it grew out of and left. Christianity leaned toward the inheritance where its parent had leaned away.

The second thing was a matter not of degree but of kind, and it is the one that bears directly on the question this post has been carrying. Judaism had refused to compromise the oneness of God's power, holding the line against any second principle. Christianity, having held that line in one place, breached it in another and a deeper one: it compromised, or transformed, depending on who is speaking, the oneness of God's very being. It developed the doctrine of the Trinity. Three hypostases, one ousia; three persons, one substance; the entire delicate Greek metaphysical machinery of Nicaea and Chalcedon exists precisely to bear the strain of confessing that the one God is three and that the three are one without, the bishops insisted, ceasing to be one.

I am not here adjudicating whether the Trinity is "really" monotheist. The Cappadocian fathers had careful and serious answers and they were not fools, and the question is a live one in systematic theology to this day. The historical observation is narrower and far harder to wave away. The strict monotheism that the post-exilic Jews fought to preserve against the Persian dualism, the absolutely single God who forms the light and creates the darkness with no other beside him and no division within him, is simply not what Trinitarian Christianity ended up confessing. To a Jew of the Second Temple, and to every Jew since, and as we are about to see to every Muslim, the doctrine of three-in-one looks like the very heresy the rabbis named, shtei reshuyot multiplied, a plurality smuggled into the godhead however subtly the theologians distinguished person from substance and procession from generation.

So Christianity's answer to the Persian question was, on the decisive point, the opposite of Judaism's. Judaism absorbed the dualist cosmology and clamped down hard on the unity of God. Christianity absorbed the same cosmology, ran it hotter, and loosened the unity itself into a Trinity, then built the most metaphysically elaborate doctrine of God in the history of the West to keep the loosening from flying apart. It walked, in its own careful and reverent way, through the door that Isaiah had tried to shut.

8. Islam recoils, and is itself a river

And then, in the seventh century, a third answer, and the sharpest of the three. To see it properly we have to begin by insisting on the thing Islam's own self-understanding most resists, which is that Islam is itself a braided river, no more sprung from a single pure source than any tradition we have traced. This insistence has a peculiar edge in Islam's case, because Islam presents itself precisely as the restoration of an original purity, the millat Ibrahim, the religion of Abraham, monotheism in its pristine form, corrupted by the Jews and the Christians who came after and now at last set right. The claim to clean origins is not incidental to Islam; it is close to its core. Which is exactly why the river deserves tracing here.

The Qur'an is saturated with the prophetic and eschatological material of the Jewish and Christian streams, inherited through the same Second Temple synthesis by way of those intermediaries. Adam and Noah and Abraham and Moses and Jesus and Mary walk through it as Adam, Nuh, Ibrahim, Musa, Isa and Maryam; the angels Gabriel and Michael appear as Jibril and Mikail; the resurrection of the dead, the day of judgement, the garden and the fire, all are present, and the bridge stretched over hell, as-sirat, across which the souls must pass, looks a very great deal like the Chinvat bridge of the Zoroastrians, narrow as a hair and sharp as a sword beneath the feet of the damned. The apocalyptic furniture is the same furniture. And after the Arab conquest of the Sasanian Empire in the 640s and 650s, Islam was in renewed and direct contact with living Zoroastrianism, the Majus of the Qur'an, a people granted an uneasy and ambiguous standing somewhere near that of the protected scriptural communities. The bell that rang first in Iranian and then in Hebrew and then in Greek and Christian registers rings in Arabic too, and from many of the same metals. Islam grew up inside the identical watershed.

But on the one question this post has carried from the start, the unity of God, Islam executed the most violent recoil of the three traditions. Where Christianity had relaxed the oneness into a Trinity, Islam made the oneness not a guarded perimeter but the whole substance and centre of the faith. Tawhīd, the absolute, indivisible unity of God, is the first principle and the non-negotiable, and its violation, shirk, the association of any partner whatever with God, is named the one sin that will not be forgiven. And the Qur'an names its targets with a directness that leaves no doubt about what it is recoiling from. Against the Trinity to its west: do not say "Three"; they have disbelieved who say that God is the third of three.¹⁰ Against the dualism the whole region had been marinating in for more than a thousand years: there is no uncreated second principle anywhere, Iblis the devil is a created being, a djinn who refused the command to bow and was damned for his pride, subordinate and finite and never for one instant a rival god.

The hammer-blow is the hundred and twelfth sura, four lines recited until they become reflex: He is God, One; the Eternal, the Absolute; He begets not, nor is He begotten; and there is none comparable to Him. Read against the long argument of this series, that sura is not a serene devotional miniature. It is a polemic, swung in two directions at once, against the Trinity to the west with its begetting and its three, and against the dualism to the east with its second uncreated power, an attempt to slam shut the door that the Persian encounter had opened seven centuries earlier and that Christianity had walked straight through. Islam's answer to the Persian question is the most conservative of the three: keep the inherited cosmology entire, the angels and the judgement and the bridge and the garden and the fire, and restore the strict monotheism whole, stricter even than the rabbis kept it, with the oneness raised from a defended boundary to the living heart of the creed.

So here, at last, are the three answers to the single question the river forced when it ran west out of Iran. Judaism absorbed the dualist cosmology and held the line at one God, keeping the furniture and guarding the oneness behind a wall it called heresy to breach. Christianity kept the furniture, ran the cosmic war hotter than its parent ever had, and let the oneness of God's own being open into three, then spent four centuries of councils learning how to say so. Islam kept the furniture too, and recoiled into the strictest oneness of all, defining itself against the Persian dualism to its east and the Christian compromise to its west in the same breath. Three traditions, one watershed, three irreconcilable settlements with the same inheritance, and each of the three serenely convinced that it alone has preserved the original and uncorrupted faith and that the other two are the deviations.

There remains one more move, and it runs the other way. We have spent this installment treating Persia as the wellspring from which the dualist apparatus flowed down into the Abrahamic watershed. But Persia is not a spring either. Zoroastrianism is itself a reform, and a reform works upon inherited material; the Wise Lord and the Hostile Spirit, the gods who became demons, the whole Iranian religious vocabulary sits atop a deeper stratum still, an Indo-Iranian religious world whose other branch ran east into India and there used the very same inherited words to mean very nearly the opposite things. The Iranian daēva, the word for a demon, is the Sanskrit deva, the word for a god. That single inversion is a window onto a common origin older than Iran and older than India, older by far than Israel, reaching back into the pastoralist communities of the Eurasian steppe in the fourth millennium before the common era. The river runs upstream still, past every tradition that has quarrelled over its waters. Part 5 follows it there.