“The theologian,” wrote Edward Gibbon in his classic The History of the Decline and Fall of the Roman Empire, “may indulge the pleasing task of describing Religion as she descended from Heaven, arrayed in her native purity. A more melancholy duty is imposed on the historian. He must discover the inevitable mixture of error and corruption, which she contracted in a long residence upon earth, among a weak and degenerate race of beings.” Gibbon was a child of the European Enlightenment, and he viewed his task as a historian of early Christianity as a dispassionate, scientific one: to see things as they are, rather than as the pious would want them to be. The conclusions he reached were, perhaps inevitably, controversial in his day. The pre-Christian Roman empire, he believed, was characterised by “religious harmony”, and the Romans were interested more in good governance than in imposing religious orthodoxy on their many subjects. A distinctive feature of early Christianity, by contrast, was for Gibbon its “exclusive zeal for the truth of religion”, a blinkered, intolerant obsessiveness that succeeded by bullying and intimidation, and promoted a class of wide-eyed mystics. Indeed, Christian zealotry, was, he thought, ultimately responsible for the fall of the Roman empire, by creating citizens contemptuous of their public duty.

Pre-Christian Rome tends to be imagined as cruel and punitive. Christianity is painted as brave and principled

This spirit permeates Catherine Nixey’s book. In her view, the standard modern picture of the Roman empire’s conversion remains, even 200 years after Gibbon, glossed by Christian triumphalism. History, she believes, has given the Church an undeservedly easy ride. Pre-Christian Rome tends to be imagined as cruel, arbitrary and punitive; it is thought to be, in her fine phrase, “a chilly, nihilistic world”. Christianity, conversely, is painted as brave, principled, kind, inclusive and optimistic. The task she sets herself – her own melancholy duty – is to rip away this veneer and expose the error and corruption of the early Church.

This is also, however, a book for the 21st century. What concerned Gibbon was the clash between faith and reason; for Nixey, the clashes are physical ones. This is, fundamentally, a study of religious violence. Her cover displays a statue of Athena deliberately damaged: its eyes have been gouged and its nose smashed, and a cross has been etched into its forehead. The story of this defacement is told in her prologue and reprised in her final words. The events happened in Palmyra in the late fourth century, when some of the oasis city’s magnificent temples were repurposed as sites of Christian worship. Her choice to begin in Palmyra is, of course, a careful one. When she speaks of the destruction wrought on the architecture of the Syrian city by “bearded, black-robed zealots”, the reader thinks not of marauding fourth-century Christian fundamentalists but of television images from recent history. “There have been,” she writes, and “there still are … those who use monotheism and its weapons to terrible ends.” What is revealing about that last sentence is not the connection she draws between savage practices in Christian late antiquity and in the name of Islamic State but the phrase “monotheism and its weapons”. Many modern commentators like to speak of religious terrorism as a horrific distortion of religious truth; for Nixey, monotheism is always weaponised and waiting only for someone to pull the trigger.

Facebook Twitter Pinterest Brutal end … Rachel Weisz as Hypatia in the film Agora, directed by Alejandro Amenábar. Photograph: Allstar/Cinebiss

The story of the destruction of Athena is the amuse-bouche for a feast of tales of murder, vandalism, wilful destruction of cultural heritage and general joylessness. We hear of the brutal end of Hypatia, the Alexandrian philosopher, mathematician and astronomer who was murdered by a Christian crowd in the early fifth century (an event dramatised in the Spanish movie Agora). Less well known, in the anglophone world at any rate, is the case of Shenoute. A contemporary of Hypatia’s, he lived further south, in rural Egypt, where he became the abbot of the complex now known as the White Monastery (which still stands in today’s town of Sohag). Shenoute is now considered a saint in the Coptic church, but his piety manifested itself in a particularly ugly guise: he was part of a gang of thugs who would break into the houses of locals whose theological views they felt to be unsound, and smash up any property they objected to on religious grounds.

Even more than the physical violence, it is the cultural devastation that draws Nixey’s eye. Early in the book, she describes how she was brought up in her youth to think of late-antique and medieval Christians as enlightened curators of the classical heritage, diligently copying philosophical texts and poems throughout the ages so that they were saved from oblivion. Her views in this matter have evidently shifted somewhat over time. In this book, early Christians are much more likely to close down the academies, shut temples, loot and destroy artwork, forbid traditional practices and burn books. Rather than praising Christians for preserving slivers of classical wisdom, she argues, we should acknowledge how much was knowingly erased.

Destroying a pagan statue or burning a book becomes a no more violent act than amputating a gangrenous limb

Where did this appetite for destruction come from? Nixey’s short answer is a simple one: demons. Many ancient Christians believed that the world we inhabit is a perilous place, crowded with malevolent supernatural beings, who sometimes manifest themselves in the form of fake gods. It is the Christian’s duty to root these out. Destroying a “pagan” statue or burning a book, then, is a no more violent act than amputating a gangrenous limb: you save the healthy whole by preventing the spread of the infection. If you think that a marble statue is possessed by a demon, then it makes a kind of sense to dig out its eyes and score a cross in its forehead. If you think, along with the North-African theologian Tertullian, that “Satan and his angels have filled the whole world” and laid traps for the virtuous in the form of sensual pleasures, then avoiding the Romans’ bathhouses, dinners and spectacles is perfectly rational – as is a disdain for sexuality. The early Christian world was in a state of perpetual metaphysical war, and choosing sides inevitably meant knowing your enemies.

Facebook Twitter Pinterest Bluff bonhomie … portrait of the Roman poet Horace. Photograph: Dea Picture Library/De Agostini/Getty Images

But demons are only half of the story. The real blame, for Nixey, lies at the door of the church fathers, whose spine-tingling sermons ramped up the polarising rhetoric of violent difference. They wove “a rich tapestry of metaphor”, construing theological opponents of all kinds as bestial, verminous, diseased and – naturally – demonic. It was language itself – the forceful, lurid language of a handful of elite males – that stoked the fires of Christian rage against its enemies, fires that blazed for a millennium: “the intellectual foundations for a thousand years of theocratic oppression were being laid.”

Nixey has a great story to tell, and she tells it exceptionally well. As one would expect from a distinguished journalist, every page is full of well-turned phrases that leap from the page. She has an expert eye for arresting details, and brings characters and scenarios to life without disguising anything of the strangeness of the world she describes. Most of all, she navigates through these tricky waters with courage and skill. Writing critically about Christian history is doubly difficult: not only are the ancient sources complex, scattered and disputed, but also there are legions of modern readers waiting to pounce on the tiniest perceived error, infelicity or offence.

Martyrdom certainly has a strangely magnetic allure, as we know from our own era

If there is a weakness in this book, it stems precisely from its Gibbonian roots. This is, fundamentally, a restatement of the Enlightenment view that the classical heritage was essentially benign and rational, and the advent of Christianity marked civilisation’s plunge into darkness (until it was fished out by Renaissance humanists). Nixey studied classics, and her affection for classical culture runs deep: she writes with great affection about the sophisticated philosophies of the stoics and epicureans, the buoyantly sexual (and not infrequently sexist) poetry of Catullus and Ovid, the bluff bonhomie of Horace and the unsentimental pragmatism of men of affairs such as Cicero and Pliny. When she speaks of classical culture and religion she tends to use such descriptions as “fundamentally liberal and generous” and “ebullient”. How, then, do we explain the Romans’ unfortunate habit of killing Christians? Nixey thinks, like Gibbon, that they were interested, principally, in good governance and in maintaining the civic order that the unruly Christians imperilled. Ancient accounts, she argues, show imperial officials who “simply do not want to execute”; rather, they are forced into it by the Christians’ perverse lust for martyrdom. Now, martyrdom certainly has a strangely magnetic allure, as we know from our own era, but the Romans were hardly bemused, passive bystanders in all of this. There is something of the zero-sum game at work here: in seeking to expose the error and corruption of the early Christian world, Nixey comes close to veiling the pre-Christian Romans’ own barbarous qualities.

But this book is not intended as a comprehensive history of early Christianity and its complex, embattled relationship to the Roman empire, and it would be unfair to judge it against that aim. It is, rather, a finely crafted, invigorating polemic against the resilient popular myth that presents the Christianisation of Rome as the triumph of a kinder, gentler politics. On those terms, it succeeds brilliantly.

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