E. A. Judge told his mentor A. H. M. Jones that he intended to “find out what difference it made to Rome to have been converted.” Jones had asked the question before, and devised a succinct response: “none.”Footnote ² His answer has not proved persuasive, and the question has occupied historians for as long as critical history has been written. Judge offered a teleological and triumphalist vision of late ancient Christianity that embraces dialectics in service of a higher, “Western” ideal,Footnote ³ while others, such as Brown,Footnote ⁴ Matthews,Footnote ⁵ Von Haehling,Footnote ⁶ MacMullen,Footnote ⁷ Van Dam,Footnote ⁸ Trombley,Footnote ⁹ Salzman,Footnote ¹⁰ Barnes,Footnote ¹¹ and BrenkFootnote ¹² have queried shifting social mores, the conversion of temples to churches, and Sunday morning head-counts in order to index the impact of Christianity on a baseline “pagan” culture,Footnote ¹³ to which Alan Cameron offered the important corrective that the “battle” between Christians and the last pagans of Rome was one-sided, at best: “While late antique Christians certainly saw themselves as engaged in a battle with paganism, what is much less clear is whether pagans saw themselves fighting a battle against Christianity.”Footnote ¹⁴

Often, modern scholars have mirrored skeptical ancient counterparts in their approach to understanding the spread of Christianity through the ranks of Rome’s elite. Augustine reports a conversation between Simplician, bishop of Milan, and the renowned Neoplatonic philosopher Marius Victorinus. The philosopher would often say to the churchman, “You know that I am already a Christian,” and the bishop would reply, “I won’t believe or count you among the Christians until I see you in a church of Christ.”Footnote ¹⁵ The philosopher offered a sarcastic response, using the Socratic method to point out the absurdity of Simplician’s assertion. Ergo parietes faciunt Christianos? “Oh, is it walls that create Christians?” For many scholars aiming to understand Christianity in the later Roman empire, the answer to Victorinus’s jest is “yes.”

Here I return to the question of Christianization, asking again, “what effect did Christianity have on inhabitants of the Roman empire in the fourth and fifth centuries?” I want to know what difference Christianity made. My method, however, diverges from the classic treatments. Rather than asking after numbers of Christians or moral renewal in late ancient Rome, I investigate the methods by which a meaningful truth claim could be made at a particular moment: during the period of flux when Christians first came to overtake state institutions with sufficient influence to effect a dramatic change on the structure of meaning-making in the Roman empire. My goal is to trace shifting practices of knowledge production in the fourth and fifth centuries, paying particular attention to scholastic sources in the domains of theology, historiography, and law.

This is to make a rather simple claim, but perhaps one with significant implications. There is no “rise of Christianity” beyond the “rise” – increase in social standing and influence – of large numbers of individual Christians. I argue that investigating a shift in the way that individual, influential Christians make arguments can offer insight into the rise of Christianity generally because during the years of the Theodosian dynasty the methods of these individual, influential Christians were taken up across scholarly disciplines by Christians and non-Christians alike, and far beyond the realm of theology.

This is a study of what counts as a fact. In trying to understand what counts as a fact, I have done what countless sociologists and historians of science did before me: go to the laboratory where facts are produced and pay close attention to their conjuring. What I’ve found is similar to what historians of science have remarked since the early days of that discipline, namely that “scientific fact is the product of average, ordinary people and settings, linked to one another by no special norms of communication forms, who work with inscription devices” in the form of “writing, schooling, printing, [and] recording procedures.” “The mysterious thinking process that seemed to float like an inaccessible ghost over social studies of science,” Latour writes, “at last has flesh and bones and can be thoroughly examined. The mistake before was to oppose heavy matter … to spiritual, cognitive thinking processes instead of focusing on the most ubiquitous and lightest of all materials: the written one.”Footnote ¹⁶

In his study of Pasteur’s work on a bovine anthrax vaccine, Latour insists that the scientist’s laboratory is a political space – political in so far as laboratory results powerfully and fundamentally changed the society into which they were unleashed. But the nature of that change is twofold, and does not consist solely in the solution to a veterinary problem. First, verification of the effect of Pasteur’s vaccine required new forms of data to be collected on a national scale and in a novel manner. Knowing whether the vaccine was effective required the expansion of statistical and quantitative methods devised in and for laboratory science to the whole of nineteenth-century French society. Second, the acceptance of such facts, and the economic benefits that compound therefrom, require a lay public to accept a new way of making arguments, presented in forms and formats previously confined to the microcosm of the laboratory. In order for a vaccine’s success to become a “fact,” laboratory methods of knowledge creation and verification needed to be governmentally operationalized and then societally accepted. Argumentative forms are notoriously fecund, in this way, escaping from the labs which create them and roaming free through a combination of top-down implementation and bottom-up opportunism.

This book studies another time when a novel form of argumentation escaped from the lab. Rather than a microcosm of the farm recreated in a Petri dish, the laboratory that I engage here attempted to form a true micro-cosmos, distilling grand questions of divine ontology to propositional statements, debating those statements, and determining their proper resolution in nuce – or in Nicaea, as it were. These scientists (or in this case we should call them “theologians,” while keeping in mind that their aims and methods were, in their own estimation, fundamentally empirical) engaged a question of how to define the nature of the deity: what god consisted in, and how the various forms that god takes relate to one another. They created an intellectual lab, overseen by the imperial government and by the deity under discussion, and yet their pronouncements could not be truly universal until and unless their form of knowledge production came to be accepted outside the theological laboratory.

Pasteur had an advantage over the scientists of Nicaea: none of his lab mates came to field trials intent on denigrating the vaccine, as was the case with dueling factions in the wake of Nicaea. Nevertheless, Pasteur’s field trials were not widely acceptable until the physical procedures of the lab were duplicated on a national scale: categorizing outbreaks through microbial sampling, isolating agents in the lab, and registering them on a standardized ledger. The acceptance of a scientific fact required the world to replicate the methods of the lab in its approach to the production of reliable knowledge. Likewise, the acceptance of a set of theological propositions in the fourth century required both the creation of new procedures for devising reliable theological facts and the widespread acceptance of those argumentative methods.

This book tells a story about the creation and implementation of a new way of making theological arguments in Late Antiquity. The forging of a new form of theological praxis is only half of the story, however. In the years after Nicene Christians came to be a ruling elite for the first time, their way of making arguments, devised in a lab and aimed at answering a particular (however cosmic) problem, became detached from the question posed and roamed free. I argue that early in the fourth century, Christians adjudicating all sides of the “Nicene controversy” forged new tools for argumentation in the fires of doctrinal controversy. While wrestling over the nature of Christ, these clerics created a new scholastic regime: new arguments were made in novel ways. By the late fourth century, when these Christians came into power as a ruling elite, their approach to truth – how it could be accessed and how it should be presented – was fundamentally different from where it began, and was even more at odds with the prevailing epistemic framework of their Roman Traditionalist neighbors.Footnote ¹⁷ Nicene Christians had invented a new book culture, but that book culture did not long remain unique to Christian scholars. When Nicene Christians came to power as a political ruling class, this peculiarly Christian argumentative structure found its way quickly into the domains of law, history, miscellany, and even Talmud. One answer to the question of “what difference did Christianity make?” is this: Nicene Christians, ascending to positions of power, changed the way that an entire scholastic culture approached the creation, verification, and dissemination of facts.

My study pays close attention to the intellectual culture of the Theodosian Age. Or, to borrow terminology from Roger Chartier’s groundbreaking work, I am interested to describe and explain historical contours of the Theodosian “order of books.”Footnote ¹⁸ My conception of intellectual culture is described well by Carlo Ginzburg’s conception of culture itself: “Culture offers to the individual a horizon of latent possibilities – a flexible and invisible cage in which he can exercise his own conditional liberty.”Footnote ¹⁹ This is the concept of intellectual culture that I invoke here: a cage, or a series of expectations, constructed through generations of precedent. The outline of the cage has an externally coherent logic; it was created in a particular place, with a particular shape, for historically contingent reasons. When later inhabitants forgot why the cage took its shape, the underlying logic moved into the domain of historical knowledge. The cage defines the boundaries of proper knowledge production. It can be flexed and punctured in places but, at least for the extent of the Theodosian Age, it remained identifiably intact.

It is possible to glimpse argumentative expectations in two places. They are visible where scholars explicitly discuss what their work sets out to accomplish, and what constitutes the boundaries of “good” work in their technical domain – a long tradition beginning at least with Aristotle, who urged writers, orators, and even flute players to preface their productions with a short discourse on method.Footnote ²⁰ Such moments of self-conscious methodological reflection are rare in ancient scholarship, but they prove illuminating when available and serve as an anchor for my discussion. Latent expectations about the structure of a good argument are visible in another place as well: in the sum total of scholastic production as it looked and was utilized in the Theodosian Age. Even when scholars are not forthcoming with plain declarations of their methodology, we can see their prejudices and intuitions in the products of their scholarship: the form in which they lay out their arguments, the way that they organize their pages, the places to which they send those pages, and the manner in which they read the work of others who they consider to be peers. If intellectual culture is conceived as a “flexible and invisible cage” that “offers to the individual a horizon of latent possibilities,” with this book I aim to describe the history of the cage itself: how it came to have the shape that it does, and how that shape defined the scholarship produced inside it.Footnote ²¹

In recent decades historians have taken the material form and social function of books as an object of study in and of itself, and as a witness to intellectual history in so far as books are created by people, in time, with purpose. The history of the book can be described as something of a punctuated equilibrium: long stretches of incremental change interrupted by moments of rupture and transition to a new order and a new set of expectations regarding what a book is, how it is to be used, and what potentialities and dangers lie among its leaves. My aim is to describe one such moment of rupture, in which widespread and durable changes in the order of books are visible across seemingly discrete domains of scholarly, technical literature. Material and literary witnesses to the later Roman empire suggest that during the Theodosian Age, scholastic elites developed a distinctly new book culture, one defined by the rise of authorized codes and implicated in the great scholarly productions of the period: the Theodosian Code, the golden age of patristic literature, the renaissance of Latin and Greek historiography, and even the Palestinian Talmud. Changes visible across the Roman literary landscape of the late fourth century played out throughout the subsequent eighty years, and in turn continue to shape contemporary notions of what books do and what one can do with books. The epistemic primacy of written sources in our contemporary world – the notion of a constitutional democracy, for instance – has roots in Rome of the Theodosian Age. In the pages that follow, I endeavor to tell part of that story of transformation.

This book, then, attempts to frame the beginning of Late Antiquity as a moment of rupture not only in politics but in praxis. It describes the transition between a late Roman world in which Christians appear as interlopers and a late ancient world in which the structures and ideologies undergirding an ascendant Christianity appear always already part of the fabric of the Jesus movement. There are other transitions to be described: turning points toward a new trajectory that cannot be linearly assimilated to what came before. My work does not describe the only beginning of Late Antiquity, but it describes an important beginning nevertheless.

My argument proceeds in stages. Chapter 1 reflects on the interconnected social world of elite readers and writers during the Theodosian dynasty, showing how they comprise a single intellectual culture expressed in different disciplinary domains. The core of the argument comprises two parts. Part I (Chapters 2–4) deals with the history of Christian argumentative forms and the creation of novel intellectual tools in early fourth century, and Part II (Chapters 5–8) considers the proliferation of those tools through diverse domains of scholarship in the late fourth through the middle of the fifth centuries ce.

Chapter 2 demonstrates the diversity of Christian approaches to truth before the Constantinian Age. I turn to Constantine and Athanasius in Chapter 3, showing the influence of each on a new way of making arguments that became widespread throughout the Orthodox Christian movement during the fourth century. Chapter 4 traces that new, Christian way of making arguments from the realm of theology into “secular” domains during the Theodosian Age, showing how a scholastic method created to solve theological problems came to be used in legal, historical, and scientific texts of the late fourth and fifth centuries.

Chapters 5–8 comprise a second unit which describes the implementation of new argumentative forms by Theodosian Age writers and readers in the ways that they approach books and in the manuscripts that they produced, copied, and used. Chapter 5 focuses on the “rise of the code” and the investiture of the codex format with new meanings when it took center stage as the preferred bookform for scholastic productions. I turn to manuscripts themselves in Chapter 6, showing first the newly instituted scholastic practices that influenced the production and use of books during the fifth century, and then detailing a number of “Christian” scribal tools that were designified and reused in “secular” manuscripts of the period in Chapter 7. Chapter 8 describes the net effect of scholastic and material changes on the way that Theodosian Age readers approached and interpreted books. A short conclusion offers reflections on the project as a whole and the reverberations that Theodosian Age book culture has had down to our present day, and an Appendix presents a detailed case study on the Theodosian Code, showing how language that was peculiar to Christian theological disputation before the Theodosian Age came to be generalized and ultimately to undergird the great juristic achievement of the fifth century.

Observations on Method

Before discussing the interimplication of scholarly domains in the Theodosian Age, I want to offer some observations on method. First, I have distilled a set of characteristics that I argue in detail are part of a class of analysis: a “new order of books.” This class definition is not exclusive: not every member of the class will possess every characteristic by which the class defined. Put differently: not every attribute of Theodosian book culture finds expression in every example adduced. My definition of a “new order of books” follows what Ludwig Wittgenstein termed “family resemblances,”Footnote ²² or what Rodney Needham calls a “polythetic classification.”Footnote ²³ As a result, the sense in which any particular example speaks to a wider book culture is not static. I hope that my reader will consider the strength of my argument overall, and the relationships between part and whole. Second, I ascribe a certain amount of agency to texts themselves – agency that compounds from the actions of writers, readers, scribes, and bookbinders, and the structure of knowledge that each imposes on or reads from the texts that they encounter. It is in this sense that texts can be agents; in their material form texts reflect some intention of their creator, and their form in turn telegraphs to subsequent users a set of argumentative expectations and practices that are related to, but not coterminous with, the intention of the creator.

Consider, for instance, a rock wall intended to delineate a property line. The wall indicates materially an imaginary legal boundary dividing an otherwise contiguous tract of land. A subsequent user of this wall may be a group of children who designate the line of the wall as one terminus in a game of hide-and-seek: in this case the intention of the wall’s creator and the later users’ understanding align to a significant degree. In Latour’s vocabulary, the rock wall in this example is an intermediary: an object that “transports meaning or force without transformation: defining its inputs is enough to define its outputs.”Footnote ²⁴ Another user of the wall, however, may be a pilot looking to align their plane with the runway ten miles ahead, who knows that the wall happens to sit on the required axis. The old intention of the rock wall remains intact even as a user, the pilot, exploits that structure to new, unforeseen ends. In this scenario the landowner’s agency has found unexpected expression in local flight paths, and that agency is mediated through a rock wall that acts as an agent itself. It is an intermediate agent, but its agency is not passive: it actively orients real-world phenomena. Again in Latour’s framework, in this instance the wall is a mediator: “Their input is never a good predictor of their output; their specificity has to be taken into account every time. Mediators transform, translate, distort, and modify the meaning or the elements they are supposed to carry.”Footnote ²⁵ These are the senses in which texts can constitute agents in the world of readers. In cases where an author’s intended use of an argument or work line up, more or less, with the way that scribes and readers actualize the material, manuscripts act as intermediaries. This is not always the case, however, because material texts often – perhaps more often than not – work as mediators instead. As Part II argues in detail, their effect on readers can be the result of authorial intention, clever reuses, or unintended eventualities. The passivity of parchment should not be mistaken for a lack of agency.

Next, a note on the sources upon which my analysis is built. The literature that I engage here is not popular; the majority of it was obscure technical literature in antiquity, and for the most part it remains so today, even among ancient historians. The “new order of books” that I describe, rooted in an argumentative method inflected by the great Christian doctrinal debates of the fourth century, did not extend to the entire population of the Roman empire in the fourth and fifth centuries; perhaps it did not extend in the form that I describe beyond the scholars engaged in intellectual debate under the Theodosian dynasty. A distinction between scholarly productions and those meant for popular consumption is not solely mine, however. This division of literary material between that which is “scholarly” or “elite” and that which is purposefully popular is visible throughout the sources. The Theodosian Code claims explicitly to be intended as a resource for the scholarly efforts “of more industrious people (diligentioribus),”Footnote ²⁶ while Ambrose affirmed to his congregation that “the faithful interpreter of the mysteries preaches more through silence” than through divulging to the masses that which is rightly the purview of the scholar.Footnote ²⁷ I hope it will become clear over the course of my analysis that the senatorial aristocracy, of which Ambrose and the jurists responsible for the Theodosian Code were part, considered each other to be peers, and intended their work to be engaged and exploited by scholars with like-minded scholastic methods, even when they held divergent substantive commitments.

And finally, a note on “method” itself. It is often observed that historical narratives predicated on case studies and close readings risk mistaking the anecdotal for the universal. At worst such studies exchange the extraordinary with the ordinary, leaving an account comprising only the most extreme termini of the system described: a picture of successive penumbral edges, failing to grasp the prosaic in light of the exceptional. My analysis responds to such critiques with the proliferation of examples, but the central concern will nevertheless remain for readers engaged in more technical, neo-formalist disciplines that ascribe particular and ultimately peculiar motivations to any work if it is scrutinized in sufficiently granular detail. I could perhaps produce an extended analysis justifying my use of particular texts and case studies in order to understand a book culture of which the selected texts comprise, at best, only a small part. Such an analysis would focus on movement in social-historical method after the so-called linguistic turn. Or, alternatively, I could offer a quantitative analysis which tabulates each and every instance of the scholastic features that I describe as they appear in Theodosian era scholastic literature. I fear, however, that either option would, in the words of Tomoko Masuzawa, “seem too intricate to be fully credible; it could appear either suspiciously obscure or improbably clever, and in the end, devious and inscrutable.”Footnote ²⁸ Instead, I have chosen to begin my project with this chapter, and end with another, in an Appendix. The first describes the imbricated nature of elite scholastic discourses during the period under analysis, while my Appendix presents a analysis of interconnections between Christian and juristic scholarship of the fourth and fifth centuries, demonstrating that the analytical method that I propose can be implemented in terms of purely philological analysis, though such a reduction will always involve loss of explanatory value. Again to paraphrase Masuzawa, the aim of this book is to excavate the half-forgotten worries, hopes, and controversies that animated a dramatic shift in the way that readers approached books and the work of scholarship during the Theodosian Age.Footnote ²⁹ I cannot ultimately justify the method on purely analytical grounds. Historical research, after all, is not science, and connoisseurship will always play a central role. I cannot hope to convince my reader of a somewhat novel method from the first pages of a long, and yet singularly interested, piece of analysis. I hope only that my reader will, for the moment, offer the benefit of the doubt, and test the utility of the analysis only after the work is complete.

Beyond Comparison

In seminal articles in the Journal of Early Christian Studies, Mark Vessey and Éric Rebillard described a new form of argumentation among Christian scholars of the Theodosian era.Footnote ³⁰ Each argued that the Theodosian Age gave rise to the phenomenon of “patristic commentary,” in which theological arguments moved from a primary basis in scriptural sources to a basis in prior theological authorities. This change in citational form was a revolution in Christian literary practice, and as Vessey has pointed out, “[i]f the conciliar and imperial enactments of 380–382 ushered in a new ecclesiastico-doctrinal order, they also heralded a new order of books.”Footnote ³¹

Scholarly description of this “new order of books” in the Theodosian era has only just begun.Footnote ³² Vessey compellingly ties the rise of new forms of Christian documentary practice to internal, Christian doctrinal disputes, arguing that new doctrinal concerns among Christians led to new textual forms. His intuition finds support in the explanation of changes in Christian documentary culture adduced by Christian scholars of the period. In 359, for instance, Hilary famously wrote that “necessity introduced the custom of defining the faith and of signing on to the definition (exponi fides, et expositis subscribi).”Footnote ³³ But the institution of new citational forms among the Christian scholastic elite did not long remain an internal facet of the Orthodox movement; in 359 the emperor Gratian was born. It was under his rule that Christians, for the first time, rose to enough prominence among the late Roman nobility that their numbers appear in rough parity with those of Roman Traditionalists in the Senate.Footnote ³⁴ According to Mark the Deacon, by the reign of Arcadius nearly all high office holders were Christian, at least notionally – he complains that “many people in positions of honor pretended to have faith” because “if the emperors learned that they did not hold rightly concerning the undefiled faith, they stripped them of honors.”Footnote ³⁵ I argue that this confluence produced broad-scale changes in the Theodosian era: the imperial decision to define the bounds of Orthodoxy as adherence to a universal statement, along with the rise of Orthodox Christians into the senatorial and noble elite at a scale significant enough to effect a fundamental change in the way that elite and scholarly arguments were made. The Christianization of the empire did not only affect public discourse on what could be true, but also how scholars went about proving the point.

In Chapter 3 I argue that this shift in scholarly practice arose from a tradition of doctrinal argumentation that found ultimate value in defining a universal statement and promulgating that statement as the bounds of Orthodoxy. It is not surprising that other forms of knowledge produced by Christians were presented with a similar structure. It is not surprising, for instance, that a Nicene Christian approach to law would privilege the subordination of a commentarial and multivocal tradition to an authorized statement of legal orthodoxy that looks something like the magisterium vitae, “guide to life,” of which the Theodosian Code was intended as a precursor.Footnote ³⁶ Yet modern scholars of Roman law have proven reticent to acknowledge any Christian influence on the structure of the Code itself, even though the majority of the men compiling Theodosius II’s law code were part of the Christian elite of the Theodosian Age, as I detail later. It is often argued, instead, that the Theodosian Code does no normative, constructive theological work, and thus it is wholly separate from other normative aspects of the Christian culture in which it was produced. I argue, however, that fourth-century debates over Orthodoxy spurred a scholastic shift that defined the contours of a book culture which influenced the Theodosian Code, as well as works such as the acta of Ephesus and Chalcedon. One may argue that the Theodosian Code is a Christian document whether or not it does constructive theological work because it is built according to scholastic specifications which arose from of Christian doctrinal dispute, an argument to which I return in the Appendix.

Contemporary scholars of each of these corpora often explain changes in the format of documents and readerly expectations during the Theodosian era on the basis of internal, disciplinary concerns. Changes in legal argumentation result from new legal exigencies, for instance, and shifts in historiographical method can be explained as resulting from an evolution internal to the ancient discipline of history. Rather like Vessey’s understanding of the advent of “patristic commentary,” scholars of rabbinic literature and Roman law habitually resist the suggestion that fundamental innovations in form could be attributable to external, cultural factors, or drift on wider scholastic currents. For example, Seth Schwartz follows generations of rabbinic scholars in arguing that “[t]he Rabbis produced a body of literature unlike anything else ever written in the Roman world. Its alienation or self-alienation from the classical tradition is nearly absolute … The Talmud’s status as Roman literature needs to be argued in ways that the status of other literary artifacts of the same time and place does not. The Rabbis proclaimed their alienation from normative Roman culture in every line they wrote.”Footnote ³⁷ A similar perspective is common among scholars of Roman law. John Matthews goes to great lengths to cobble together an answer to the question of why, “at this late hour in Roman history [429 ce],” a codification of law should be undertaken. Matthews admits that “with the Theodosian Code … we find ourselves at such a moment, when a need is felt to make this clear, to sum up an achievement because it forms a part of the perceived aims of a state or because these aims are threatened.”Footnote ³⁸ Along with the vast majority of scholars of Roman law, Matthews steadfastly refuses to consider that the “need” for a clear summation of legal Orthodoxy arose only within Christian intellectual culture in which such universal statements of truth, distilled from commentarial and discursive traditions, were in fact quite commonplace. By the time of the Code’s promulgation, Christian scholars had undertaken similar efforts as their central scholastic aim for nearly two generations. Despite an admitted paucity of evidence, Matthews contends instead that political expediency and general unease with the state of the law in the mid-fifth century animated the compilation of the Code.Footnote ³⁹ He repeats an orthodoxy among scholars of Roman jurisprudence when he presents the Theodosian Code as an utterly novel innovation.

In and of themselves, internal explanations for changes in documentary culture and citational practice are not wrong, or even misguided. But in this instance, such explanations fail to account for one simple datum: remarkably similar changes to documentary practice took place across all domains of scholarly literature during the Theodosian Age. It may be the case that similar innovations in the presentation and utilization of textual material coincidentally occurred across traditions simultaneously. However, I argue that in this instance broader changes in cultural expectations of texts – what they are, what the look like, and what they do – simply found varied expressions in different scholarly genres. These cultural expectations were forged in the Christian doctrinal controversies of the fourth century and codified in the great literary achievements of the fifth. And, importantly, the changes are not limited to the form of arguments, but extend to the format of scholastic manuscripts from the period, as I demonstrate in Part II.

This is to say something that, on its face, is rather uncontroversial: that the theologians, jurists, rabbis, and assorted scholars of technical disciplines responsible for the literary remains of the Theodosian era are not sui generis. They were educated alongside peers of elite households, and share reading habits and hermeneutic strategies.Footnote ⁴⁰ Some of these men went into imperial administration, while others went into Church administration. Some argued Christological points with compendia of previous theological debates and pronouncements; many more argued legal points with compendia of previous laws and analysis. Theologians created dossiers of conciliar pronouncements and acta while jurists created compendia of legal statutes and juristic opinions. In the case of two corpora – dossiers of conciliar acta and compendia of legal statutes and juristic opinions – both were compiled in the same court chancery, likely by the same imperial officials.

As Susanna Elm notes of the Emperor Julian and Gregory of Nazianzus: “Both were entirely men of their time. They shared with each other and their elite contemporaries far more than divided them.”Footnote ⁴¹ The same could be said of a great number of elite men engaged in late ancient scholarly disciplines. As Blossom Stefaniw rightly observes: “To study Christians according to specially Christian categories … is to reinscribe and reify early Christian ideologies of novelty and singularity.”Footnote ⁴² It is also to write history between self-imposed blinders. Cognate literatures offer a window on the structure of readerly and writerly expectations, and scholarly disciplines on either side of the redescriptive divide of “theological/secular” are cognate literatures, indeed.

This is, I hope, not to flirt with parallelomania. I do not want merely to show that the concerns of one corpus are echoed in another. It is hardly surprising that in some aspects the acta of Chalcedon and the Theodosian Code share similar concerns. Further, it is not surprising that the Palestinian Talmud, a quasi-legal code compiled in the late fourth century, would hold some ideas or issues in common with the other great legal codification of its day. Rather, I attempt to demonstrate convergences between these corpora on a structural level – to show that Theodosian Age scholars approached their task of commentary and codification with analogous prejudices and expectations about scholarship. These prejudices and expectations were new to the Theodosian era, widespread, and durable.

A note on terminology: my distinction between “Christian” and “Juristic” scholarship is not meant to imply that jurists could not be Christians, or that their Christianity was ancillary to their judicial work. Quite the opposite: this book purposefully militates against such bifurcation. Rather, I use the terms in their disciplinary sense: “Christian scholarship” refers to a tradition of theological disputation that the subjects of my analysis considered to have a definite form of internal coherence. For instance, for Jerome, “Christian scholarship” includes works of the 135 men whom he deemed “eminent” (illustres) in his explication of the tradition, whether he agreed with their substantive commitments or not.Footnote ⁴³ There is no doubt that Jerome conceived of juristic scholarship as a separate domain from the discourse of Christian scholarship exemplified by his “eminent men”: he says as much in Letter 77.3, on which I have more to say later. Many centrally important jurists of the Theodosian court were Christians, and their Christianity influenced their scholarly production in the same way that Ambrose’s legal training inflects his own works of Christian scholarship. Likewise there is no doubt that the professorship of jurisprudence endowed by Theodosius II and Valentinian III in 425 was awarded to a professing Nicene Christian.Footnote ⁴⁴ But this man’s professional duties were nevertheless cast within the realm of juristic scholarship. “Christian scholarship” and “Juristic scholarship” were conceptually separable domains of inquiry during the Theodosian Age, and each had an idea of their own disciplinary history. Both were equally domains of scholarship, or what Caroline Humfress has called “specialist form[s] of imperial prose literature.”Footnote ⁴⁵ When I distinguish between “Christian” and “Juristic” work in the Theodosian empire, I invoke this emic distinction.

One intention of this book is to clarify the extent of interimplication of scholastic domains in the Theodosian Age, especially between Christian and juristic scholarship, but also including other areas of literary expertise: history, medicine, military science, and Jewish law. Because of the nature of the comparison and the nature of contemporary scholarship on each domain, I proceed through my argument in two steps. I begin by focusing on the shared book culture evident in of the Theodosian Age which was primarily undertaken by Christians and Traditionalists, distilling from the extant sources an overview of the “new order of books” as well as specific, discrete innovations that populate the literary landscape of the late fourth and fifth centuries. I turn to rabbinic sources only at the end of my analysis, offering a reading of the Palestinian Talmud in Chapter 7 contextualized by the convergences visible between scholarship in the other domains of Theodosian scholarship. I have two reasons to proceed in this manner. First, avenues of exchange, to which I turn shortly, are significantly clearer between theologians and jurists than among any other scholastic group. The extent and nature of their contact is explicit. On the other hand, as Schwartz argued earlier, rabbis formally disclaim the type of cultural influence that we can see between theologians, jurists, and a wider Roman book culture. The nature of exchange among scholars in the domains of theology, law, history, etc. is reasonably clear; in the case of the rabbis, contact is somewhat more diffuse, and perhaps involved less reciprocity between groups.

Second, this is a book with a comparative methodology, and as such it is particularly prone to muddy waters in which the distinctiveness of corpora dissolve into a puddle of similarity without obvious implication. Comparison is always carried out with reference to a background of similarity, between three objects of inquiry.Footnote ⁴⁶ In order for a comparison to have useful implications, two objects must be compared on the basis of a single substratum of identity. In this case, comparison between scholars working in and around the various imperial courts will help to clarify the substratum of identity, which I identify as components of the “Theodosian order of books” – facets shared between the technical literature of each that arose from a shared intellectual culture. Subsequent comparison with rabbinic material offers a crucible in which to test hypotheses regarding the scholastic environment of the later Roman empire, and its separate discussion is intended to guard against the multiplication of exempla that disbands any useful or rigorous basis for analysis. Only after establishing a “new order of books” can the concepts that it comprises be used as a basis upon which to ask whether rabbinic material truly takes part in the same book culture as other literate Romans in the Theodosian Age. If the Roman rabbinic material, in turn, shares distinctive aspects of Theodosian book culture that differ from what is found in other instantiations of the genre, like the Sassanian recension of the Talmud, then such correlations point to a distinctive and shared book culture between scholars of all stripes living in the later Roman empire.

Theologians and Jurists

I am hardly the first historian to suggest that theologians and jurists benefited from similar training, and that they brought to their divergent tasks a similar textual habitus. Texts from the Theodosian Age demonstrate this clearly. For instance, the Collatio legum Mosaicarum et Romanarum comprises an importation of Roman juristic writing and legal pronouncements into a Christian framework, and amply demonstrates its compilers’ interest in rectifying Roman juristic and biblical scholarship as separate but compatible domains of inquiry.Footnote ⁴⁷ Jerome, too, speaks regularly and learnedly of the Roman juristic tradition, expecting his interlocutors at least to understand his references, such as one in Epistle 77 (399 ce), where he announces that “Caesar’s laws differ from Christ’s. Papinian prescribes one thing, and our own Paul another.”Footnote ⁴⁸ Augustine too shows at least general familiarity with the documents and institutions of legal scholarship when he quotes from a law of Caracalla as preserved in the Codex Gregorianus, and discusses elsewhere the Senatus consultum de bacchanalibus.Footnote ⁴⁹ Caroline Humfress concluded that “Augustine, like Jerome, thus rejects the writings of the Roman jurists in favour of the teachings of Christian Scripture, yet both patristic authors are thereby able to showcase their own elite familiarity with Roman legal culture.”Footnote ⁵⁰ I would modify Humfress’s conclusion only slightly, stressing that what we find in these intertexts is not just “elite familiarity with Roman legal culture.” Rather, we come to see that seamless movement through elite Roman culture itself required cursory training in law.Footnote ⁵¹ I hope to demonstrate that theologians shared not only judicial training; they also think about the production and use of scholarly books in a similar manner to their jurist peers.

Lines of transmission, however, do not lead invariably from the elite, “secular” culture of law to the specialized, “sacred” culture of Christian theological disputation. Noel Lenski has shown conclusively with a case study on the Arian controversy that the distinction between doctrinal and legal disputation had already become meaningless by the beginning of the fourth century, during Constantine’s own reign:

One hundred years before the compilation of the Theodosian Code, when the empire, by the most generous estimates, was around 20 percent populated by people identifying as Christian, civic and theological disputation were already opposite sides of the same Constantinian coin. By the time that more Christians were members of the Roman senate than Roman Traditionalists another half century had passed, Theodosius I had ascended to the purple, and a new era of Christian and juristic scholarship was on the horizon. John Matthews argues that it was precisely the early years of the reign of Theodosius I in which we see the full dissolution of any meaningful distinction between the emperor’s religious and legislative agendas.Footnote ⁵³ I add here that the distinction between agendas fails to mark a difference, but so does a distinction between imperial staffs. Members of both Theodosian Code commissions corresponded extensively with disputants on either side of important theological debates of their day, and were present and active at the Council of Chalcedon. The “Christianization” of juristic practice is visible not only in the way that the men responsible for writing and promulgating law identified themselves religiously, but also in the text of legal statues themselves, as one sees with even a cursory overview of the mid-fourth-century anti-Traditionalist laws preserved in book sixteen of the Theodosian Code.

My book, then, uses the methods of book history to produce a history of practice, showing how intellectual formats and argumentative tools conceived to answer thorny theological questions became detached from their institutional home and inflected other scholarly disciplines in the period after Nicene Christians came to be a ruling elite for the first time. I intend to bear out with a study of practice what Lewis Ayres has seen through intellectual history, namely that “Christian theology should be seen not as a separate branch of late antique knowledge, with a content separate from other branches of knowledge, but as itself a means of structuring the activity of knowing overall. In particular, the development of Nicene theology offered new ways for Christians to articulate both the task of knowing and its goal.”Footnote ⁵⁴ In Chapter 5 I turn to “the rise of the code”: authoritative, scholarly distillations of authorized material as found in Christian and juristic sources. The code, however, did not arise in a vacuum. Both exogenous and endogenous factors created the environment in which codification seemed necessary, especially among Christian scholars dealing with the aftermath of the so-called Arian controversy. A change in argumentative practices forms the backdrop for the rise of the code during the time of Athanasius and beyond into the Theodosian Age, when “patristic commentary” began to displace more traditional formats based in scriptural citation as the central avenue of scholarly argumentation. But there is a story of development and difference, of continuity and rupture in scholarly practice, to be told in the centuries leading up to the fourth, when Christians first began to think systematically and dogmatically about the place of authoritative text in theological disputation. Followers of Jesus did not always agree – in particular or even in broad strokes – regarding the proper method by which one might make a true theological statement. I turn now to this contentious history of Christian proof.