built these principles out of a range of received teachings. Especially foundational was the biblical notion that a man and woman become “one flesh” through sexual intercourse (Genesis 2:24). Christian thinkers understood this as a divinely decreed, essentially indissoluble ontological status—hence Jesus’ teaching against divorce, “what God has joined together, let no one separate” (Matthew 19:6, Mark 10:8–9). Equally significant was Paul’s insight that, given the divine institution of the singleness of flesh, any sex outside of a monogamous marital union was fornication (porneia), inherently defiled and defiling (1 Corinthians 7).14 Finally, strands of Stoic philosophy contributed to the early Christian imagination the conviction that if sex within marriage was lawful, it was so only for reproduction rather than for pleasure, wage labor, or any other purpose.15
These perspectives defined late antique Christianity’s theology of conjugal, chaste sexuality. In the centuries before Christianity became the official religion of the Roman Empire, they were a radical departure from a Greco-Roman sexual culture in which divorce was relatively simple and extramarital sex with dishonorable bodies (slaves and prostitutes) had been perfectly acceptable for men. The circumscription of licit sexual activity to the single, indissoluble, procreative marital bond was thus a major innovation.16 It was also a practical one, in the sense that it provided householders who could not achieve perfection in virginity or continence a means to ensure their worthiness of salvation. The Greek and Latin Church Fathers (John Chrysostom and Augustine are two major exemplars) constructed this message in a substantial body of theological literature, much of it admonitory and for lay consumption. Little has been written on the theology of lay marriage in the early Syriac traditions of the Christian east, our main area of interest. In general, early Syriac writers like Aphrahat (fl. fourth century) and Ephrem (d. 373) contemplated the virtues of virginity extensively while devoting less attention to worldly marriage,17 although they invested great significance in an ecclesiology of marriage according to which the church looks forward to union with Christ the bridegroom in the world to come.18 When late antique churchmen of the Syriac traditions did consider the theological dimensions of marriage, they offered a formulation of chaste, procreative sexuality likely deriving from the synthesis of biblical, Stoic, and Aristotelian perspectives found in the writings of Clement of Alexandria (d. 215).19 In a nutshell, marriage for them was the divinely instituted, rational ordering of sexuality for procreative purposes that distinguished humans from non-rational animals. In Jacob of Serugh’s (d. 521) homily On Virginity, Fornication, and the Marriage of the Righteous, for example, sexuality outside the framework of procreative marriage is associated with subhuman, non-rational animals:
Anyone who remains in virginity is of the spiritual ones, and anyone who walks the path of the righteous [i.e., the married] is of the holy ones;
but anyone who descends to fornication is of the animals. Of the one [human] race there are three classes of people.
Among them are those who walk in virginity with the spiritual ones, in the path higher than worldly ways.
Others take the path of the righteous with marriage, the path pure of blame and censure.
Others descend to fornication, the wicked life, and resemble beasts and animals.20
Virginity is the highest degree of spiritual achievement to Jacob, but a rational sexuality within marriage, distinct from the random mating of animals, is still a mark of righteousness. The East Syrian patriarch Mar Aba (r. 540–52) gives a more definitive if less poetic expression of the same ideas. Mar Aba describes marriage as the institution “which God has established [sāmēh] for admirably administering the maintenance of our nature and the succession of our lineages [yubbālā d-sharbātan], not in the likeness of beast[s] lacking discernment [law ba-dmut bʿirā d-lā purshānā], but in an order that suits rational beings [b-ṭaksā d-ʿāhen la-mlilē].”21 Here we find the core elements—marriage as the ordered facilitator of the procreation of rational humans, as opposed to non-rational animals—of a characteristically late antique Christian conception of licit sexuality within the confines of the marital relationship.
LAW, MARRIAGE, AND RELIGION IN THE LATE ANTIQUE EMPIRES
The Roman Empire
The connection between sexuality and salvation spurred Christian thinkers in the empires of late antiquity to define the elements of Christian marriage—monogamy, indissolubility, and the restrained practice of sex. These ideas departed in several key respects from accepted norms in the Roman world, especially in their dramatic narrowing of the horizons of licit sexual practice. But in fact, Christian theology was only one of several normative orders that claimed the authority to govern the ancient institution of marriage and the domestic and familial relationships associated with it. These orders overlapped and interlinked in significant ways, but they remained distinct and Christian perspectives on sex and marriage never achieved absolute predominance within them. As a result, the reception of those perspectives by lay populations across the Roman Empire, as well as in Sasanian territory, was halting, uneven, and incomplete throughout late antiquity and into the medieval period.22
The most significant of the normative orders with which Christian thought interacted in this respect were the imperial and local traditions of civil law that governed the formation, maintenance, and dissolution of marriage as a legal institution.23 In the Roman Empire, this meant Roman law above all else, as well as its provincial iterations. An ancient and venerable imperial tradition, Roman law set the norms that governed relationships among persons, groups, and the state, in areas ranging from family law to property law to criminal law; it defined procedural rules for state organs; and it represented the will and authority of the emperor, his officials, and imperial institutions.24 In the area of the family, Roman law regulated the contracting of marriage, the transmission of property connected to it, and the other points at which citizens’ conjugal life intersected with the public arena.25 Indeed, Roman emperors had a long track record of legislative intervention in the affairs of Roman families and households (which, as elsewhere in the premodern world, were not necessarily coterminous because households often included slaves and other dependents in addition to biologically related family members). These legislative programs aimed to tie the citizenry to the imperium’s wider interests and ideological commitments. The trend began with Augustus at the turn of the millennium; it continued in Constantine’s highly novel legislation in the fourth century and, especially, Justinian’s massive legal codification project and Christian “moral activism” in the sixth.26 Significantly, however, Christian perspectives on sexuality were incorporated into Roman civil law only very partially, even as late antique emperors and jurists came to frame that law as divinely inspired and founded on Christian authority.27 Overall, Roman law continued to recognize as perfectly lawful many of the acts—chiefly divorce, remarriage, and men’s extramarital affairs with low-status women—that constituted unchaste, defiled sexuality in the Christian vision. Divorce is a particularly telling case. Constantine restricted the classical doctrine, which had allowed unilateral repudiation by either spouse without cause. His successors variously eased and reimposed restrictions; but all of this may have been motivated more by the need to regulate marital property exchanges than by Christian morals. Justinian, on the other hand, took the unprecedented step of prohibiting consensual divorce for two spouses who simply did not want to remain married, which was certainly a Christianizing reform in the context of his broader project of imperial regeneration. Yet this reform was so far outside the bounds of centuries’ worth of common practice that Justinian’s successor quickly rescinded the prohibition.28 Thus, across its tangled path of development and even in its partially restricted late antique form, the Roman legal doctrine of divorce never came close to the ecclesiastical ideal of indissolubility. From late antiquity into the medieval period, the Christian model of marriage continued to compete with old social mores encoded in or tacitly sanctioned by the civil legal structures of the Roman Empire.
Ecclesiastics had two principal
