In the Shadow of the Sword: The Birth of Islam and the Rise of the Global Arab Empire

Joined at the Hip

Huge buildings spelled greatness. The Caesars had always appreciated this. Like the issuing of laws, the humbling of barbarians and the wearing of purple, the construction of towering monuments was very much part of what the Roman people expected of an emperor. Nor was Justinian minded to let them down. Even before the destruction of large swaths of Constantinople provided him with the perfect opportunity to rebuild the city to his own exalted tastes, he had displayed his relish for the empire’s grand tradition of architectural swagger. The initial focus of his energies, however, had lain not in the capital but far away, on the eastern frontier.

Here, in 530, the Persians had responded to the latest breakdown of peace talks in time-honoured fashion—by making a land grab. The object of their campaign had been that particular bugbear of their high command, Dara. Directly in front of the walls of the fortress, a Roman army, led by a brilliant young general named Belisarius, had met the Persians and put them to flight. “Such an event was one which had not happened for a very long while.”⁴⁰ Nevertheless, it had been a close-run thing: Dara’s fortifications, jerry-built at immense speed, would not have withstood a concentrated siege. “And because the emperor Justinian perceived that the Persians, so far as it lay in their power, would never permit this outpost of the Romans, which was such a menace to them, to continue standing there, but were bound to persist in attacking it with all their might,”⁴¹ he had ordered a massive rebuilding programme.⁴² Dara was made to bristle. It was designed to be—and to appear—impregnable. Any passing barbarians were to look on it and despair. The emperor, aiming to ram the point home, even graced Dara with a new name: “Justiniana New Town.” Here, in the hulking silhouette of its ramparts, was the manifestation of a ruler with the world in his hands.

Or so he liked to think. In fact, the message conveyed by the militarisation of the frontier was altogether more ambiguous than Justinian might have wished. The rival pretensions of Dara and Nisibis, frowning at each other across the Mesopotamian flat-lands, could easily seem to make a mockery of both. “The nations are like a drop from the bucket, and are accounted as the dust on the scales.”⁴³ So it was written in the Tanakh. The Jews, lacking any empire of their own, treasured a distinctive perspective on international affairs. It reassured them that the great kingdoms of the world, despite all their clamour and posturing, were accounted by God “as less than nothing and emptiness.”⁴⁴ They knew that the true division of the world was not the one proclaimed by the battlements of Dara, between Roman and barbarian, but something quite else: between those who lived in the manner ordained by the Almighty and those who did not.

Given this, who was to say that the scattering of the Jews far beyond the limits of their ancestral homeland was not all part of the heavenly plan? “By your descendants,” God had told Abraham, “shall all the nations of the earth bless themselves.”⁴⁵ This assurance had long prompted many Jews to ponder the immense distances that separated them from the Promised Land, and to arrive at a daring conclusion. As one rabbi, back in the time of Constantine, had put it with forthright conviction, “The Holy One, blessed be He, exiled us among the nations in order that converts might swell our ranks.”⁴⁶ This, it might have been thought, was rather to contradict the emphasis that the Almighty had placed on the significance of Abraham’s bloodline; but it was also to assert that “Jewishness,” in the final reckoning, was determined less by blood than by obedience to the demands of the Torah. Accept that, and the Jews did certainly appear well placed to reshape the world. Mesopotamia was certainly far from being their only home away from home. Few were the points of the compass where they were not to be found. They had become, in a sense, more truly universal than any empire. Rather like the Greeks, they ranked not merely as a people but as the agents of a culture, of an entire way of understanding, interpreting and refashioning the world. The awesome power of their ferociously demanding God, the staggering antiquity of their laws, and the glamour of what seemed to many less a faith than a private members’ club: all had combined to make the Jews objects of rare fascination to those among whom they lived. Unsurprisingly, then, there was a venerable tradition of their admirers becoming “proselytes”—“which is to say, people who have been made into Jews.”⁴⁷ In Rome, the imperial authorities had been fretting about such conversions since the time of the republic. A whole succession of emperors had sought to regulate what they saw as a palpable and growing menace. A century and a half before Constantine, the circumcision of converts had been declared equivalent to castration: a crime that would see the perpetrator exiled to a desert island. Faint consolation to the Jews themselves though it might have been, there was testimony here to their faith’s profound appeal. The superstitions of conquered people were rarely honoured by the Roman elite with such hostility. The resentment and indignation of the rulers of the world were nothing if not a form of tribute.

But how, precisely, was a Jew to be defined? It was to answer this question, of course, that the rabbis of Mesopotamia, back in the time of Ardashir, had founded the famous yeshivas of Sura and Pumpedita, and embarked upon the great project of research that would culminate in their transcription of the Talmud. Mesopotamia, however, was not the world. No matter what the rabbis themselves might care to think, most Jews were largely oblivious to their existence. For the first few centuries after the founding of the yeshivas, the scholars who taught in them were more interested in ensuring that they were listened to in their own backyard than in establishing a global voice. Across the eastern reaches of Iranshahr itself, in much of the Roman world, and in the deserts and mountains that lay beyond the reach of both empires, rabbis were signally lacking. Authority lay instead with the leaders of what had come to be known as “synagogues.” These were communal meeting places where the Torah was studied and debated, and where Jewishness—Ioudaismos, in Greek—was rarely a given. Different communities, and different individuals, tended to define it much as they pleased. Often, it might seem as though the definition of a Jew was simply someone who described himself as such. Consequently, the boundary that demarcated Jews from non-Jews—“Gentiles,” as they were called—was never entirely stable. One Jew might take the high road that led to Persepolis and there, on the lintels of that Zoroastrian holy place, carve a summons to the people of Iranshahr to join his faith;⁴⁸ another, panic-stricken at the thought of falling for the insidious attractions of foreign women, and thereby jeopardising the purity of Abraham’s bloodline, might try and avoid so much as stealing a glance at a Gentile. Even the rabbis, despite their burning ambition to distinguish themselves and their people as rigidly as possible from the world beyond, found it impossible to agree on who precisely qualified as a Jew. Some argued that proselytes were fully Jewish. Others maintained that they were “as injurious as sores.”⁴⁹ Neither side found it possible to establish a definitive answer. They had no option, so it seemed to the rabbis, save to agree to disagree.^b

Except that there did exist another option. Long before the founding of the great rabbinical schools of Mesopotamia, in an era so distant that even the title of “rabbi” itself had only tentatively begun to be employed, a small group of Jews had made a spectacular announcement: that a notorious troublemaker by the name of Jesus, recently crucified and supposedly risen from the dead, was none other than the “Christ.” More than that, indeed—that this same Jesus was also, in some mysterious manner, the Son of God Himself. These Christians—as they soon came to be known—had not initially thought of themselves as any the less Jewish for holding these startling beliefs. Nor had it ever crossed the minds of most of them that the Torah, that incomparable framework for living granted to His Chosen People by the Almighty Himself, might conceivably have been rendered redundant. Yet there were some, pushing the implications of their new beliefs to radical limits, who had soon arrived at precisely such a conclusion.

A few decades on from Jesus’s crucifixion, a group of Christians in Asia Minor received a letter that positively seethed with scandalous notions. Its author, a one-time student of the Torah called Paul, was the most spectacular rebel that the famously prescriptive Jewish educational system had ever bred. “There is neither Jew nor Greek, there is neither slave nor free, there is neither male nor female; for you are all one in Christ Jesus.”⁵⁰ In this revolutionary proclamation, Paul deftly cut what had always been, for Jewish scholars, the ultimate Gordian knot. No need, so Paul announced with a flourish, to pick at the problem one moment more. Whereas once it had been the Torah which gave to the Chosen People their roadmap to the purposes of God, now, with the coming of Christ, the need for such a Law was gone. The whole question of what it was that made for a Jew had been dissolved into irrelevance. No longer was there any obligation to follow the Torah’s rulings, to be bound by its strictures, to attend to all its endless finger-wagging: “Now that faith has come, we are no longer under a custodian; for in Christ Jesus you are all sons of God, through faith.”⁵¹ The Gentiles too, so Paul had concluded, were heirs to the promise made by God to Abraham. No longer were the Chosen People defined by a lineage of blood, or by adherence to a law, but by the knowledge and love of Christ. Nations everywhere, in short, might now be ranked as the children of Abraham. All it needed was for the entire world to end up Christian.

Which, as mission statements went, could certainly not be faulted for any lack of chutzpah. Paul’s ambitions were quite as ground-breaking as they were global. Cults, and the divinities they celebrated, had hitherto invariably been local: attached to specific places, attached to particular peoples. Any suggestion that they might be something more, that they might be universal, was liable to strike most people as either offensive, or ludicrous, or both. Nevertheless, Paul had indeed breathed in something of the authentic spirit of the age. Enthusiasm for a brotherhood of man was increasingly in the air. Posidonius, after all, a whole century before Paul, had trusted that it would emerge as one of the fruits of Roman rule. Why, then, in a world dominated by the pretensions of would-be universal empires, should the pretensions of a would-be universal faith not find a ready audience? Sure enough, in the decades and centuries following Jesus’ crucifixion, the Christian mission to the Gentiles began to thrive. Cells planted in the time of Paul steadily renewed and replicated themselves. Across lands ruled from Ctesiphon, across lands ruled from Rome, they grew, and flourished, and spread. In each one, men and women from every conceivable background, class and race would meet as equals, in a shared room, before the gaze of a severe but loving God. Equals, because all of them—the senator no less than the kitchen-maid, the Greek no less than the Briton, the philosopher no less than the whore—might be sucked down into the glutinous bog of sin; equals, because all of them, thanks to the death of Christ upon the cross, had been rendered capable of winning salvation for themselves. Never before had there been preached a message of personal responsibility quite so radical, so democratic, or so potentially wide-reaching in its appeal. Christian thinkers, in their struggle to define the principles of their faith, were engaged in a project no less well-suited to the times for being so palpably quixotic: the fathoming of the purposes of God in an ever more globalised world.

In this respect, of course, they were not so far different from the rabbis of Mesopotamia. Their methods were similar, too: for Christian sages also drew for their ultimate inspiration upon the inheritance of Jewish scripture. However, whereas the rabbis identified the Torah as something ageless and unchanging, Gentile Christians viewed it—and the Tanakh generally—merely as an “Old Testament”: a cloud-dimmed glimpse of the Eternal Light that was Jesus Christ. This perspective, of course, begged an obvious question: what should a “New Testament” be?⁵² Already, in the century that followed Christ’s crucifixion, scholars had begun to compile collections of writings that could provide an answer. Paul’s letters were the first to be anthologised, and then various euangelia, or “gospels”—biographies of Christ. Just like the rabbis of Sura and Pumpedita, the Christians who compiled these texts believed that it had been given to them to meditate upon the single most earth-shattering event in human history: an intrusion of the divine into the fallen world so cosmic in its implications that the entire order of the universe revolved around it. The surest fruit of this intrusion, however, was not a body of law, as the rabbis believed, but rather the knowledge in the soul of an individual believer that Jesus was truly the Lord. “I am the way, and the truth, and the life.” So Christ, according to one of the gospels, had declared. “No one comes to the Father, but by me.”⁵³

A ringing statement—but ambiguous all the same. It was given to few Christians to claim, as Paul himself had done, a personal vision of the risen Christ. How, then, in the absence of such direct communications, were the faithful to know what, precisely, “the way” might be? Jesus himself, when commanding his followers to “make disciples of all nations,” had instructed them to do so “in the name of the Father and of the Son and of the Holy Spirit.”⁵⁴ Here, however, was only further ambiguity—for who, or what, was “the Holy Spirit”? The answer to this question, one that many generations of Christian sages would labour at providing, did not come easily: for it touched upon the ineffable mystery that was the identity of God Himself. How fortunate it was, then, for the less intellectually inclined among the faithful, that the Holy Spirit might be experienced without necessarily being comprehended. Whether imagined as a dove, or as fire, or as a sound “from heaven like the rush of a mighty wind,”⁵⁵ it was, so Christians believed, the very breath of the divine upon the world. Whenever they felt themselves moved by the rapture of faith, a flickering-like ecstasy about their souls, then they could know themselves possessed by the Spirit. Not, however, that the evidence of its workings was confined to their inner lives. The Spirit was to be traced as well in the unity that it brought to the Christian people everywhere. No matter where these men and women might live, no matter what their status, they had all shared a single ceremony of initiation: an immersion in water that they termed “baptism.” “For by one Spirit we were all baptised into one body—Jews or Greeks, slaves or free—and all were made to drink of one Spirit.”⁵⁶ Without it, there could be no unity, no shared Ecclesia—no Church.

Which meant in turn that Christians everywhere could throw themselves into the business of constructing a globe-spanning bureaucracy and feel that they were thereby serving the purposes of their Lord. A relish for firing off letters was yet another way in which Paul had blazed a trail. Long-distance communications were cherished by the faithful throughout the Roman and the Iranian worlds as the lifeblood of the Church. The most trivial, as well as the most transcendent, topics were vigorously debated by Christians across the entire sweep of the rival empires. Not even a Caesar, not even a Shahanshah, could boast a perspective to match. Christians, well aware of this, positively gloried in the fact: “Any country can be their homeland—and yet their homeland, wheresoever it may be, is to them a foreign place.”⁵⁷ There seemed no limit to the expanding scope of their identity.

Yet it was not only by thinking on a global scale that the Christian Church had succeeded in fashioning itself, over the course of barely a few centuries, into the most formidable non-governmental organisation that the world had ever seen. It operated locally as well. Little more than a generation after Jesus’s crucifixion, Christians had already grown obsessed with the need for disciplined book-keeping. The paperwork of each individual church had duly been entrusted to an official chosen by the local congregation to serve as an “overseer,” or “episcopos”: a “bishop.” Soon enough, however, and these same bureaucrats had begun soaringly to outgrow their origins as mere functionaries. Three centuries on, and it had become the entitlement of a bishop to rule almost as a monarch over the congregation that selected him. He it was who would act as spokesman for local Christians in their dealings with the broader Church; move to resolve their problems and defend them in times of crisis; define for them their beliefs, and prescribe for them the texts they should read, and answer for them before God. “It is manifest that we should look upon the bishop even as we would look upon the Lord Himself—standing, as he does, before the Lord.”⁵⁸

Here, then, was authority such as even a Roman or a Persian aristocrat might appreciate. Although bishops tended to shun the silks and jewels beloved of the upper classes, the coarse wool of their robes could not disguise the fact that they too, like any great magnate, dealt ultimately in patronage. “If you would be perfect, go, sell what you possess and give to the poor.”⁵⁹ This injunction of Christ’s, while not always followed to the letter, had nevertheless inspired among Christians a tradition of charity that was capable of providing bishops, the men who administered its fruits, with immense reserves of largesse. In city after city, the Church had come to constitute not merely a state within a state but something altogether more exceptional: a welfare state. In a world where there were few safety nets for the destitute, or the widowed, or the sick, this might serve to endow the local bishop with an often brilliant aura of holiness—and holiness, to the Christian people, spelled power. Much, in turn, was bound to flow from this. With power, a bishop could impose discipline upon his flock; and with discipline, the Church could maintain itself as something truly universal—as “catholic.” Three centuries on from the lifetime of Christ, and there was nothing that would have borne a surer witness to the glory of His triumph over death, and to the workings of the Holy Spirit, than a Christian people who stood as one.

Certainly, as their propagandists never tired of pointing out, there was nothing in all the bewildering kaleidoscope of idolatrous cults that could remotely compare with the sense of common identity that most Christians did authentically share. That did not mean, however, that the Christian people enjoyed a perfect unity. Far from it. The world remained a realm of sin, and the body of the Church, as that of Christ had been upon the cross, was racked and twisted by the tortures inflicted upon it by the wicked. Not everyone who laid claim to the name of Christian was necessarily willing to acknowledge the authority of a bishop. “Beware of false prophets,” Christ Himself had warned, “who come to you in sheep’s clothing but inwardly are ravening wolves.”⁶⁰ Food for thought—for how to tell a sheep from a wolf disguised inside a fleece? Writing in Carthage, a famous and wealthy city in North Africa, a Christian philosopher by the name of Tertullian had proffered some helpful advice: “It is the sources and the originals of the faith which must be accounted the truth.”⁶¹ Nothing was to be reckoned authentically Christian, in other words, that could not be traced, generation back through generation, to the time of Christ Himself, and of His first followers, the apostles. If this was true for doctrine, Tertullian argued, then so also was it true for priests. Any bishop who stood in a line of succession from one of the original apostles served as the heir of a Christian who had been blessed by the hands of the Son of God. What better pedigree than that? “For, undoubtedly, it preserves what the churches received from the apostles, the apostles from Christ, and Christ from God.”⁶²

A clinching display of logic, it might have been thought—except that other Christians too could play the same game. Formidable and peerless though the organisation of the self-proclaimed “catholic” Church might be, it was not alone in looking back to the primal origins of the faith to sanction its doctrines. Indeed, there was a sense in which the very efforts of its servants to carve a straight path through all the wilds of potential belief—an “orthodoxy”—served only to open up alternative routes. The existence of a linked network of bishoprics across the span of the known world reflected an understanding of Christ’s teachings that had been shaped, above all, by Paul: an understanding that viewed the Church as a body universal, defined by faith rather than law, and ablaze with “the power of the Holy Spirit.”⁶³ All these presumptions, however, might readily be challenged. Why, for instance, should the Church not remain what it had been back in the very earliest days of its existence: a pure body of the elect, small to be sure, but untainted by the outside world? And how was it, if the Torah were a matter of sublime irrelevance, as Paul had taught, that Christ Himself had so emphatically stated the exact opposite: “till heaven and earth pass away, not an iota, not a dot, will pass from the law until all is accomplished”?⁶⁴

Even this, however, was not to touch upon the profoundest, the most dizzying, the most perplexing question of all: what precisely was the relationship of the Holy Spirit to Christ, and of Christ, the Son of God, to His Heavenly Father? Once again, it was Tertullian—never one to shirk a challenge—who provided the most widely accepted answer. God, he explained, was Three: Father, Son and Spirit. Likewise, these three aspects of the divinity—the creator, the redeemer and the inspirer—were One. A paradox, of course—but one that Tertullian, who had not been expensively schooled in the subtleties of Greek philosophy for nothing, saw as expressive of the very essence of the divine. God, who was Three in One, and One in Three, was best thought of, he explained, as a Trinitas—a “Trinity.”

Yet even Tertullian, despite the triumphant swagger with which he had made his case, had been under no illusion that he had proved it: “The mystery stays guarded.”⁶⁵ Which was putting it mildly. Any number of slippery issues still remained to be pinned down. If God were truly One, for instance, did that mean the Son was not, as His title implied, subordinate to the Father but in every way His equal? The tendency in orthodox circles was increasingly to answer “yes”; but the fact that this implied a Son who was no less eternal than His own parent, an apparent illogicality that had worried Tertullian himself, ensured that there were plenty of Christians who scorned to agree. This, of course, in a Church where there were few means of enforcing a specific orthodoxy other than by exhortation and argument, they were perfectly at liberty to do; and it ensured that the spectrum of Christian beliefs held by the Christian people, rather than narrowing as time went on, came instead to embody a quite bewildering range of shades. It was all very well for the likes of Tertullian to argue that an impregnable mystery lay at the heart of the faith; but there were many Christians who found it difficult to leave the matter simply at that. Too much was at stake. The irreducible message of the Christian faith—that God, through the agency of Jesus, had somehow intruded into the mortal fabric of human flesh—raised as many questions as it answered, not only about the essence of the divine but about who precisely Jesus might have been. Equally God and equally man: such, three hundred years after the crucifixion, had come to be the favoured orthodoxy among the leaders of the Church. But it was not the only one. There were some Christians who argued that Jesus had been completely divine, with not a trace of the human about him. There were others who claimed that his body had provided a mortal shell for the heavenly Spirit, which was presumed to have descended upon him during his baptism, and abandoned him before he died on the cross. There were still others who insisted that Jesus had been the adopted Son of God—flesh and blood, like any other man, but no less the Christ for that. Not a permutation of beliefs, in short, but some group of Christians, somewhere, might choose to subscribe to it.

And it was precisely this range of opinion—hairesis, in Greek—that drove those who wished to affirm a single orthodoxy to distraction.^c Of course, every Christian sect liked to imagine that its own understanding of Christ constituted the way, the truth, the life; but it was the self-proclaimed “catholic” Church, by virtue of its sheer scale, which had the most weight to throw around. The most to lose as well if it did not. Painstakingly, over the course of the centuries, it had set itself to the formidable task of clearing any number of doctrinal booby-traps from the feet of the faithful. Understandably, then, its scholars and leaders had little patience for those who would sabotage such a project. Christians who rejected the Church’s authority were increasingly viewed not as fellow travellers but rather as souls lost upon crooked paths, agents of error who had wilfully chosen to abandon the one, true road of orthodoxy—as “heretics.” Nothing they touched so sacred or so precious, but they would attempt to sabotage it. “For their behaviour is exactly like that of someone who, when an exquisite mosaic of a king has been fashioned by a great artist out of rare stones, takes the mosaic completely to pieces, and rearranges the jewels, and puts them back together to make the image of a dog or a fox—and a poorly executed one at that.”⁶⁶

Such bitterness was hardly surprising. The efforts made by generations of Christian scholars to establish the truth of what Christ might have said and done had indeed been as punctilious as those of any master-mosaicist. Only the most finely calibrated measuring-rod—a canon, in Greek—had been deployed for the purpose. Just as was required by the most exacting standards of the historians of the day, no gospel had been passed as “canonical” that could not be shown, to the satisfaction of catholic scholars, to derive from the authentic evidence of eyewitnesses to the events described.⁶⁷ Increasingly, only four such gospels—two attributed to disciples of Jesus; one to a disciple of Simon Peter, the chief of the apostles; and one to an associate of Paul—had come to be regarded as measuring up. Yet still, a hundred, two hundred, even three hundred years after the crucifixion, biographies of Christ continued to be cranked out. Of course, gospels such as these, composed at such a remove of time, could hardly have any great claims to biographical accuracy; but biographical accuracy, to those who composed them, was hardly the point. For many writers, the motivation might be as simple as a desire to entertain, by telling fabulous stories, and filling in some obvious gaps. What kind of games, for instance, had the infant Saviour enjoyed while playing with His friends? A host of gospels had not hesitated to provide the answer.⁶⁸ Christ’s favourite stunt as a child, so it was revealed, had been to make clay birds, breathe on the sculptures, and then bring them to life. Not, perhaps, quite as edifying an anecdote as those to be found in the four canonical gospels—but innocent enough, certainly. Other adjustments to Christ’s biography, however, might be altogether more momentous in their implications. Some, indeed, might strike directly at the heart of Christian orthodoxy.

When, for instance, a Christian named Basilides wished to demonstrate that Jesus had not died upon the cross, he made good the complete lack of evidence for this novel theory in the canonical gospels through a simple expedient: he wrote a whole new gospel of his own.⁶⁹ The story of the crucifixion, in Basilides’s reworking of it, contained a hitherto unsuspected twist. Christ, as He was carrying His cross through the streets of Jerusalem, had magically swapped bodies with Simon of Cyrene, a man who had come to His assistance. As a result, it was the unfortunate Simon who had been crucified. Christ Himself, meanwhile, watching from a safe distance, had stood “roaring with laughter.”⁷⁰

But how precisely had Basilides come by this startling revelation? No less than his adversaries, he had perfectly appreciated the vital importance of pedigree. A gospel was nothing unless it could be traced back to a heavyweight informant. This was why, in offering to the world his account of the crucifixion, Basilides had made sure to attribute it to the classiest, the most impeccable source he could find: Simon Peter himself. Critics of Basilides, however, snorted at this claim as grotesque. Any notion that details of Christ’s life and teachings might have been kept secret from his mass of followers and passed down only among a privileged few, was dismissed by them out of hand. The claims of Basilides to a privileged gnosis, or “knowledge”—one supposedly denied to less enlightened Christians—was dismissed by his orthodox opponents as the merest braggadocio. After all, as they never tired of pointing out, he was only one of a swarming, buzzing crowd. There were any number of “Gnostics,” all with their own pretensions, all with their own scriptures. “The Church has four gospels, but the heretics have many.”⁷¹ That being so, how could any of them be trusted? All were clearly fabrications. None could plausibly be attributed to an apostle. Certainly, Basilides’s laughable insistence that his gospel derived from a succession of whispered reminiscences, passed down from generation to generation and never even once put into writing, was precisely what served to brand it a fraud: “For it is evident that the perfect truth of the Church derives from its high antiquity; and that all these many heresies, being more recent in time, and subsequent to the truth, are nothing but recent concoctions, manufactured from the truth.”⁷²

Except, of course, that any rabbi, contemplating the pretensions of the Gentile Church, might well have made an identical point. The Tanakh, after all, long pre-dated even the earliest gospel. Christian thinkers, as they struggled to establish the parameters of their faith, were often rendered profoundly uncomfortable by this reflection. So much so, in fact, that one of them, a bishop’s son by the name of Marcion, was brought by it to take the ultimate step, and deny that he owed anything to the Jews at all. Rather than acknowledge the umbilical cord that linked the gospels to the Old Testament, he simply cut right through it. Christ, so he taught, shared nothing, absolutely nothing, with the Jewish god. One preached love and mercy and occupied the upper storeys of heaven; the other issued endless laws, punished all those who did not obey them, and smouldered away in the lower reaches of the sky. Some Christians, struck by the awful logic of this, were sufficiently convinced by Marcion’s teaching to establish a whole new church; others, the majority, shrank from it in horror. All of them, though, as they wrestled with the question of who or what Christ might have been, were wrestling as well with the issue of what their relationship to the Jewish past should properly be. If Jesus were truly the Messiah, then the failure of God’s Chosen People to recognise that fact could rank only as a monstrous embarrassment. Self-evidently, however, the blame for such a scandal had to lie not with Christ but with the Jews themselves. Increasingly, then, the claim of the Gentile Church to embody the fulfilment of the Jewish scriptures required it to scorn the rival claims of the synagogues as thunderously as possible: “For I declare that they of the seed of Abraham who follow the Law, and do not come to believe in Christ before they die, will not be saved.”⁷³ The Torah was a dung-heap; its students pickers after trash; all its great array of dictates a mere monument to desiccation. Never before had there been an attempt at disinheritance on quite so audacious a scale.

The rabbis, rather than dignify the Gentiles who would rob them of their patrimony with a direct rebuttal, opted instead to hold their noses and maintain a dismissive hauteur. “Let a man always flee,” as one of them sniffed, “from what is repellent.”⁷⁴ Nevertheless, even in their mightiest strongholds, even in the yeshivas, a rising tide was lapping at their feet. The danger signs had long been there to see. Christians were hardly a novelty in Mesopotamia. Indeed, they had originally arrived on its borders around the same time as the first emergence there of the rabbis themselves. Though Paul, back in the age of the apostles, had travelled westwards—to the cities of the Greek world, and to Rome—other missionaries had soon begun to turn their gaze towards the rising sun. The roads of the Fertile Crescent, after all, were quite as open as the sea-lanes of the Mediterranean. Already, by the time of the founding of the Mesopotamian yeshivas, in the early third century AD, there had come to exist, a mere two weeks’ journey north of Sura and Pumpedita, a formidable stronghold of Christian sages—and one that lost nothing in comparison to the schools of the rabbis.

Like Harran, its immediate neighbour, Edessa lay on the fault-line between the rival empires of Rome and Persia; but unlike Harran, which positively revelled in her idolatrous reputation, Edessa was famed among Christians everywhere as the “Blessed City.” Christ Himself, so it was said, had penned a missive to one of her kings. The very document itself was still to be found in the city’s archives: sure proof against scepticism. Nor was that all. Edessa laid claim to an even more sensational souvenir of Christ’s correspondence: His only known self-portrait, painted and sent by Him, so it was said, in response to a royal fan-letter. No wonder, given these indubitable marks of divine favour, that Christians should have believed that Edessa was destined never to fall. Certainly, the protective sympathy extended by her rulers towards the Church had enabled the city to become a veritable hot-house of Christian scholarship. The hymns, and the prayers, and the translations written there would serve to make Syriac, the language spoken by the Edessans, the lingua franca of the entire Christian Near East.

As the rabbis hunkered down inside their own schools, the influence of Edessa was already palpable in the streets that stretched beyond their walls. All very well for the rabbis to meet this challenge with an icy show of silence—but that hardly served to make it go away. A Christian, after all, was likely to have none of the compunctions about converting a Jew that a Jew might have about converting a Christian. Increasingly, in the competition between the two faiths for proselytes, it was clear which one was winning.

Yet mortal though the enmity between the rabbis and the leaders of the Gentile Church had certainly become, it was haunted by paradox. Relations between these two implacable rivals were shaped by a truth that neither could possibly acknowledge: both, in their struggle to define themselves, had need of the other. The more that Christians scorned the Jews as a people unchanged from what they had ever been, clinging blindly and obdurately to the wreckage of a superseded faith, so the more, ironically enough, did it serve to burnish the rabbis’ self-image. Here, from their bitterest opponents, was confirmation of their own most prized conceits: that they were the guardians of a timeless law; that there was no hint of novelty attached to their current project; and that the ancient prophets—Daniel, Abraham, Adam—had all been rabbis exactly like themselves. Christians, however, were not the only ones to have given their foes an involuntary boost. The rabbis, by refusing to engage in open combat with the Christian heretics, were effectively declaring that the minim no longer ranked as even faintly Jewish—and not to rank as Jewish was, of course, to a rabbi, a truly terrible fate. This, however, was not at all how the minim themselves saw things. The only effect of Jewish scorn on a Gentile bishop was to boost his self-confidence, and flatter his pretensions. “Do not marvel,” Christ had declared, “that I said to you, ‘You must be born anew.’ ”⁷⁵ To the Gentile Church, the sense of itself as a daughter sprung from the womb of a withered and unregenerate mother had become a precious conceit. Just as the rabbis had every interest in dismissing Christians as bastard and unwanted spawn, so did Christians have no less an interest in casting the faith of their Jewish contemporaries as the failed parent of their own. Both, though, were wrong. The relationship between the rival faiths, that of the rabbis and the bishops, was not one of parent and child. Rather, it was one of siblings: rival twins, doomed like Romulus and Remus to mutual hatred, yet bred all the same of the identical womb.⁷⁶

And there were still places, to the disgust of both rabbis and bishops, where a strong sense of this endured. Three centuries on from the supposed arrival in Edessa of Christ’s letter, and there were few better spots from where to gauge the potentially infinite variety of human belief than “the Blessed City.” To stand on its citadel and gaze around at the horizon was, for a Christian sage, to be conscious of just how various was God’s creation. To the east was the empire of the Persians; to the west, that of the Romans. On the margins of the first, in Khorasan, it was the habit of “a single man to take many wives”; on the margins of the second, in Britain, “many men together take a single wife.”⁷⁷ The glory of the Christian faith, so it seemed to the scholars of Edessa, was that it provided all of humanity with a means of transcending such differences of custom: of giving people, no matter where they lived, one common identity as the children of Abraham. Yet what was the Christian faith? To lower the gaze from the distant horizon, to look down into the teeming warren of Edessa’s streets, was to doubt that there could be any single answer. There were some Christians walking the city who followed the doctrines of Marcion, and others who denied that Christ had suffered on the cross, and others yet who believed that the four earliest gospels should be read in the form of a single digest. To be sure, there was no lack of Christians either who were proud to account themselves members of a worldwide, orthodox Church—and yet their traditions were no less fiercely local for that. In every Christian community, not just Edessa, the cast of what people believed, and how they behaved, might be influenced by much more than their bishop. The festivals that were held in a city’s streets, the languages that were spoken in its markets, and the stories that were shared around its evening fires: all might serve to influence the character of its Church. This was why, in Edessa and in cities across Mesopotamia, it mattered a very great deal that the Jews were people of flesh and blood, and not mere faceless bogeys. They might be neighbours, colleagues—even friends.⁷⁸ The Christians of the East, almost without realising it, bore the unmistakable stamp of this. Certainly, to visitors from other Churches, they were liable to appear quite disconcertingly Jewish.

In Mesopotamia, for instance, Christians still refused to eat meat that had not first been drained of all its blood, exactly as prescribed by the Torah.⁷⁹ They celebrated the resurrection of Christ on a date arrived at by a specifically Jewish method of calculation.⁸⁰ Even the title by which they habitually addressed their priests—rabban—sounded similar to, and had the same meaning as, rabbi. Granted, none of this implied any sense of kinship between Jewish and Christian leaders. Quite the contrary: the rabbis’ and priests’ consciousness of what they shared only made them all the more determined to draw rigid dividing-lines between their two faiths. Yet, in reality, those dividing-lines were often blurred. In Edessa, for instance, the mutual obsession of Jewish and Christian scholars with one another’s labours bore a particularly spectacular fruit: for the first translation of the Old Testament into Syriac was most likely made, not by Christians at all, but by Jews, who then subsequently converted and made a gift of their work to the Church.⁸¹ Yet in truth, to many Jews, it was not always apparent that an acceptance of Jesus as the Messiah did necessarily require them to stop being Jewish. Likewise, among the ranks of Christians, there were many who persisted in obeying the Torah and who regarded Paul, not as a saint, but rather as “a renegade from the Law”⁸²—the heretic of heretics. Some, indeed, saw no contradiction in hedging their bets even more comprehensively by invoking both the One God of the Jews and the Trinity of the Christians simultaneously. “By the name of I-Am-That-I-Am, the Lord of Hosts,” as one particularly all-inclusive curse ran, “and by the name of Jesus, who conquered the height and the depth by his cross, and by the name of his exalted father, and by the name of the holy spirits forever and in eternity …?”⁸³ Well, then, might those who sought to patrol the dividing-line between the two faiths have been appalled. “It is monstrous to talk of Jesus Christ, and yet to behave as a Jew.”⁸⁴ This assertion had been made by a celebrated saint of the early Church, Ignatius, a man supposedly appointed bishop of the great Syrian city of Antioch by Simon Peter himself; and yet it might just as well have been made by a rabbi. Jewish and Christian leaders alike, both had the same frontier policy: to create a no-man’s land. Both were equally threatened by an open, porous border.

Not, of course, that to plug one was necessarily a simple task. Those who lived in the Fertile Crescent could appreciate this better than most. The line that separated the empires of Persia and Rome did not, after all, follow the course of a natural barrier. Instead, it wound across featureless landscape, and divided peoples who more properly belonged together. Only with muscle, and resolve, and ceaseless effort could such a boundary possibly hope to be maintained. That Edessa, which in AD 216 had been formally annexed by Rome, would still remain, three centuries on, a possession of the Roman Empire, bore witness enough to the ability of the Caesars to hold a line.⁸⁵ Though Kavad, in 503, would put the city under siege, Edessa would not, unlike Amida, fall. Justinian’s great building programme at Dara, a hundred miles to the east, would serve only to hammer home the point. It took might to maintain a border. Might such as only the master of a mighty empire could command.

Two centuries and more before the time of Justinian, however, neither rabbi nor bishop wielded any such power. Great though the moral authority of both had become among the communities which they claimed to lead, it certainly did not extend to the building of watchtowers, to the manning of a frontier. Jews and Christians, though conscious of themselves as peoples with distinct identities, remained unclear where precisely the border between them lay. Jewish Christians and Christian Jews could still mill across it pretty much as they pleased.

Only a man who could lend to the rabbis or the bishops the full awesome power of a Shahanshah, or perhaps a Caesar, could hope to alter that.

But such a prospect, in AD 300, seemed scarcely imaginable.