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Law in the Early Christian Church

The early Christian Church began with a body of norms—rules regulating behavior—that sought to guide its members and help individual communities navigate questions confronting its faithful. Over time, these norms would evolve into a body of law.¹ The Old and New Testament and the writings of the Patristic Fathers who addressed matters pertaining to the Christian community serve as the earliest sources for these norms. As the Christian community grew in size, geographic scope, and complexity, church councils—attended by bishops, clergy, and secular officials—would become important forums for resolving matters involving both the shepherd (priest) and his flock (faithful). By the end of the fourth century, the bishop of Rome would see his influence grow as he was consulted by other bishops regarding all sorts of matters pertaining to the Church. His responses, papal decretals, would become a source of authority. Scripture, the writings of the Church Fathers, conciliar canons, and decretals served as manuals to guide the clergy and the laity. The Christian community necessitated some rules and regulations for the orderly conduct of its business, to define the functions of its officers, and to govern relationships among its members. Alongside these sources, Roman emperors of the fourth century, in particular Constantine and Theodosius II, would have a tremendous impact on the status of the Church, and Roman law would serve as a secondary source for the canonical tradition. Norms that regulated Christian monasticism would also complement the canonical tradition. Monks, nuns, and monastic communities would become a counterpoint to the secular clergy as the Middle Ages progressed. Collectively, these sources of norms and civil law would form the foundation for canon law as their texts would be recopied into the canonical collections that began to appear at the turn of the fifth century.²

1 A. Thier, “Dynamische Schriftlichkeit, Zur Normbildung in den vorgratianischen Kanonessammlungen,” ZRG Kan Abt. 93 (2007): 1–33.2 B. Ferme and G. Falchi, Introduzione allo studio delle fonti dell’Utrumque Iuris (Vatican City, 2006), 32–36 provides an introduction to the special place held by Scripture, and tradition as set out in apostolic and pseudo-apostolic writings, councils, and papal letters. Supplementing these sources are Roman law, theological texts, monastic rules, writings of the Church Fathers and saints, and histories (pp. 36–39).

Scripture and the New Testament, in particular, serve as the earliest sources for Christian norms. They were aimed at maintaining discipline among church members and concentrated on the internal concerns of the group. Of particular importance were the Gospels and the letters of the apostle Paul. Both reflect a climate in which Christian communities throughout the Roman Empire struggled to survive in a hostile environment. Jewish communities rejected Christian claims about the Messiahship of Jesus, deplored the conversion of Jews to the new faith, and were scandalized by the failure of those converts to continue observing the prescriptions of Mosaic law. Many Gentiles were equally unwelcoming to the new religion, but for different reasons. Pagan intellectuals dismissed Christian claims to have received divine revelations as irrational, while government authorities suspected Christians of criminal, perhaps even treasonous, conspiracies. Ordinary people found the ascetic habits of Christians peculiar and resented their rejection of the social bonding involved in the celebration of the civic festivals of the pagan religious calendar. Because Christians had constituted a small, close-knit, secretive group who habitually kept to themselves and shunned intimate contact with the surrounding society, hostility toward them soon hardened into open persecution. This began as early as the reign of Nero (54–68), who found the Christians convenient scapegoats for the great fire at Rome in 64 CE and for other civic discontents. Persecution continued sporadically until the abdication of the emperor Diocletian (284–305), who made the liquidation of Christianity one of the major goals in his program of imperial renewal. In such an environment, Christian norms centered largely on internal matters, such as the order of worship, relationships among members of the community, and the rights and obligations assigned to different subgroups among the members. Rules governing these issues seem to have been formulated by bishops and other community leaders, and presumably represented some sort of group consensus about appropriate behavioral norms.

The apostolic tradition—both real and dubious (apocryphal)—was compiled into collections of regulations for the use of church authorities, and appeared quite early in the Church’s history. The earliest surviving handbook, the Didache or Doctrine of the Twelve Apostles, dates from the end of the first or the beginning of the second century. This brief work—it is scarcely more than pamphlet-size—consists of a series of moral precepts, followed by prescriptions for the conduct of liturgical services and a handful of rules about church governance. The Didache was soon followed by more ample explanations of the basic rules that governed conduct in early Christian communities. The second-century Pastor of Hermas seems more apocalyptic than a book of norms. It consists of five “visions” or revelations, a dozen rules of conduct, and ten parables on eschatological themes. The Traditio apostolica, ascribed to Hippolytus, appeared early in the third century. Its author, whomever he may have been, claims that his book transmits the genuine doctrine of the apostles and warns that deviation from that tradition will lead to doctrinal error and heretical beliefs. While the subject matter of the Traditio apostolica is chiefly liturgical, it also contains valuable information about the organization and structure of the third-century church. The mid-third-century Didascalia apostolorum incorporates much of the material in the Traditio apostolica, but adds further information about such matters as the Christian community’s responsibility for widows and orphans, Jewish–Christian relations, and rules on fasting and penance, as well as liturgical matters.³

3 See J. Gaudemet, Les sources du droit de l’église en Occident du IIe au VIIe siècle (Paris, 1985) and, more briefly, L. Roger, “Law, Canon: To Gratian,” in DMA, 7:395–413.

The Patristic Fathers who followed on the heels of the apostolic tradition were bishop-theologians who directly engaged in issues facing the local and wider Christian community. Basil of Caesarea (d. 379), Gregory of Nazianzus (d. 389), Gregory of Nyssa (d. ca. 395), Jerome (d. 419/20), Ambrose (d. 397), and Augustine of Hippo (d. 430) are among these Fathers. Their writings would be absorbed by and shape the canonical tradition. Augustine, in particular, would prove tremendously important. His thoughts on law, politics, and orthodoxy can be found throughout his body of theological writings. He distinguished between eternal law (God), natural law (a “notion” of eternal law “impressed on human beings”), temporal law (secular law that can change over time and vary by place and circumstance), and divine law (sometimes interpreted as Mosaic law and other times considered as any laws passed down by God). He used scriptural ideas in his City of God as a lens through which to elucidate the relationship between Christians and civil government and the role the former should undertake in the secular world. Augustine’s views on what constituted a just war and the roles to be played by both ecclesiastical and secular officials laid the foundation for legal thought on the subject for centuries.⁴ His extensive writings on matters concerning the faith and against heretical movements—namely, Arians, Manichaeans, Donatists, and Pelagians—shaped the Church’s views toward deviations from mainstream teachings and doctrine. Augustine’s writings demonstrate how Patristic Fathers, though not concerned with creating “law”, nevertheless developed behavioral norms that shaped a sense of group identity and created a social order that bound and regulated the Christian community.

4 See B. Gronewoller, “Augustine of Hippo,” in Great Christian Jurists and Legal Collections in the First Millennium, ed. P. Reynolds (Cambridge, 2019), 268–282; E. M. Atkins and R. J. Dodaro, Augustine: Political Writings (Cambridge, 2001); H. E. Six-Means, Augustine and Catholic Christianization: The Catholicization of Roman Africa, 391–408 (New York, 2011) is particularly helpful for placing Augustine within the wider cultural, political, and religious climate of the time.

Patristic Fathers, such as Augustine, developed the norms for regulating the Christian community and also found themselves in the position of enforcing those very norms that bound its members. From the reign of Constantine, Christian emperors explicitly recognized the jurisdictional authority of bishops and other church officers over issues that involved doctrine and morals and gave their decisions the force of public law.⁵ The bishops’ court, the audientia episcopalis, adjudicated ecclesiastical matters and, as healers of the community friction, facilitated civil dispute settlements through arbitration, negotiation, and mediation. Since canon law had not developed its own distinctive rules governing evidence and procedure in contentious matters, episcopal courts by and large adapted for their own purposes the norms found in Roman civil law. The details of this adaptation, however, are obscure and the scanty surviving sources give the impression that procedures varied considerably between different regions and perhaps even between different judges in the same region. Also varied were the types of cases the ecclesiastical courts of this early period would hear as the boundaries of their activity were not neatly defined. Some cases only involved the church or clergy; other cases were civil in nature.⁶ What we can say is that the judicial functions of bishops in this early period mainly centered on arbitration; they typically sought to resolve conflicts by mediating between the parties rather than imposing judgments from on high. In some situations, however, canonical judges felt obliged to penalize members of the church either for heinous moral lapses or for beliefs that challenged the authority of orthodox leaders. The audientia episcopalis and other church tribunals, particularly councils and synods, asserted penal jurisdiction over deviations from the Christian faith to combat the threat of heresy. The audientia episcopalis laid a foundation for canon law to be vested with coercive power, as well as moral authority, and for the ecclesiastical hierarchy it, in effect, became an arm of the judicial apparatus of Roman government.

5 Cod. Theod. 1.27.1–2, see The Theodosian Code, trans. C. Pharr (New York, 1952).6 N. Lenski, “Evidence for the Audientia episcopalis in the New Letters of Augustine,” in Law, Society, and Authority in Late Antiquity, ed. R. Mathisen (Oxford, 2001), 83–97.

Beginning as provincial synods in the second century and expanding to include gatherings of the entire Church in the fourth century, councils were the third forum from which ecclesiastical norms emanated. As the letters of the apostle Paul suggest, councils originated as venues for the local churches to regularize and correct the behavior of church leaders and community. By the mid-third century, as examples from Africa and the Eastern Roman Empire suggest, gatherings of bishops, priests, deacons, and laity played an important role in clarifying matters of practice and teaching, such as the date of Easter, the validity of baptisms performed by sects, and the emerging beliefs that differed from the mainstream. The collective actions of councils saw the value of developing uniform procedures and policies. This shift from strictly local concerns to a collegial body drew from the Roman cultural norm of consensus, i.e. not necessarily unanimity. Councils also drew upon the four stages of Roman parliamentary procedure: presentation of the issue (relatio); voicing of participant viewpoints (sententiae); voting on a resolution created from the sententiae; and the recording of the decisions. Councils could also take the form of debate/dialogue or could be convened by the order of the emperor. By the fourth century, councils had become institutionalized and ubiquitous.⁷ As the conciliar movement consolidated, they tended to address the discipline of the clergy, administrative regulations pertaining to the clergy and holy orders, and regulations for the laity. The Iberian council of Elvira (ca. 306) is the earliest-known council for which decrees survive. The canons address the sexual behavior of the clergy and laity, translating bishops and clergy to other churches, and episcopal visits to the imperial court.⁸

7 H. Hess, The Early Development of Canon Law and the Council of Serdica (Oxford, 2020), 5–38.8 Ibid., 93–209 for an introduction to the council and an analysis of the subjects addressed; pp. 211–255 for the original text and facing English translation.

Councils gathering clergy from all of Christendom addressed, among other issues, questions regarding the nature of Christ and deviations from orthodox teaching.⁹ The first such council was that of Nicaea (325) which Emperor Constantine convened to address the teachings of the priest Arius who believed that only God the Father could be unbegotten and un-generated. Since God made Christ, he was neither co-equal, nor co-eternal, nor co-substantial with God. The resulting Nicene Creed, still recited today, held that Christ was equal to the God, they share the same substance, and neither existed before the other. The First Council of Constantinople (381) banned the teachings of Bishop Apollinarius of Laodica who maintained that Christ had a human body and a human soul but no human mind. He was born from Mary knowing everything and thus had no moral development. The council determined that if Christ was not a complete man, he could not save the whole of human nature (mind, body, and soul). In 431, the Council of Ephesus banned the teachings of Nestorius, the archbishop of Constantinople, who maintained two separate natures in Christ: one divine and the other human. The council determined that Christ was at once God and man with both these natures operating freely in him. Also condemned were the teaching of the British theologian Pelagius, who held that there was no original sin and man could take the initial steps towards salvation by his own efforts. The Council of Chalcedon banned the belief of the Monophysites in 451, which held that Christ possessed only a divine nature. The council concluded that Christ had two natures: one divine and one human. Councils would emerge in the fourth century as legislative bodies and would become a source of law, doctrinal pronouncements, and spiritual guidance.

9 For the following councils, see COGD I. A translation can be found in Tanner, vol. 1.

The Church in the fourth century had begun to develop an organizational structure whose main features still endure to the present day in Roman Catholic Christianity. That structure is hierarchical; that is, authority and responsibility within the organization are distributed unequally among functionaries according to their rank or position.¹⁰ Priests and other ministers among the lower clergy enjoy limited authority over the laity within a small geographical region that came to be known as a parish. Parish priests are responsible to a bishop, who supervises a larger region, called a diocese. The bishop has the right to impose rules on his priests and to discipline or remove those who fail to obey them. The bishop, in turn, is subordinate to a metropolitan or archbishop, whose authority extends throughout a still larger region, called a province, which includes several dioceses. Each bishop must answer to his metropolitan for the conduct of the priests and laypersons within his diocese and the metropolitan has the authority to prescribe rules that the bishops subordinate to him must follow. Metropolitans, in turn, are responsible to even higher authorities, the patriarchs, who may supervise church affairs in several different kingdoms. The First Council of Constantinople (381) recognized the bishops of Alexandria, Antioch, Constantinople, Jerusalem, and Rome as patriarchs.¹¹ Among these five patriarchs (collectively called the pentarchy), the bishops of Rome not only claimed patriarchal authority throughout the Western Empire, but also asserted that they possessed a preeminent authority over the other patriarchs, a claim that made the Eastern patriarchs uneasy.

10 Prior to the fourth century, the structure of the Church was more collegial rather than hierarchical. Christianity was concentrated largely in cities and that community, over which the bishop presided, was often referred to by the name of that city (e.g. Alexandria, Corinth, Ephesus, etc.). Priests and deacons assisted the bishop, who was chosen by the members of the local church, but as the sole pastor of all the Christians within his city he was not formally responsible to any higher authority outside of it. The subordination of authority occurred in the fourth century when the Church was integrated into the administrative system of the Empire. For a fuller discussion, see M. Fahey, “The Catholicity of the Church in the New Testament and in the Early Patristic Period,” The Jurist 52 (1992): 44–70.11 First Council of Constantinople, cc.2–3, in COGD I:20–21.

Due in part to the claims to special authority that they had begun to assert over the other bishops of the Christian world, by the fifth century the bishops of Rome began to take a more prominent role as a source of ecclesiastical law. Papal decretals, or rescripts, were letters, in which the Roman bishops responded to questions posed to them, usually by other bishops, regarding church doctrine, governance, and discipline. The earliest preserved decretal (385) was that of Pope Siricius (384–399), who responded to a letter received by his predecessor Pope Damascus (366–384). Bishop Himerius of Tarragona had written to the bishop of Rome asking for guidance on the proper practices and seasons of the liturgical year for baptism, whether those who were baptized into a heretical sect should be re-baptized, the treatment of Christians who lapsed into paganism, admissions to the minor and major orders, the punishment of monks and nuns who have fornicated, what to do with married priests and deacons who had children with their wives after their ordination, and questions regarding penance. Papal decretals through the end of the fifth century tended to respond to questions about rituals and liturgy, ecclesiastical hierarchy and authority, celibacy, “bigamy” (that is, remarriage after being widowed or marriage to a widow, both of which prohibited a man from entering the priesthood), marriage, heresy, heretics’ return to the orthodox church, and penance. The popes structured these rescripts in a fashion echoing the charters and letters of Roman emperors and imperial officials.¹²

12 D. d’Avray, Papal Jurisprudence c.400: Sources of the Canon Law Tradition (Cambridge, 2019).

The Roman legal tradition co-existed alongside the writings of the Church Fathers, conciliar canons, and papal decretals. The Theodosian Code, for example, was published in the eastern half of the Roman Empire in 437 and in the western half in 438. It contains imperial constitutions from Constantine I until Theodosius II in 437, and reflects the extent to which imperial laws were concerned ecclesiastical governance and discipline. It brought together imperial laws with the works of the classical Roman jurists by uniting all Roman law while removing obsolete laws and eliminating contradictions. The period of persecution of Christians had ended with the accession to power of Constantine I (306–337). He and his successors—with the exception of Julian the Apostate (361–363)—transformed the relationship between the Christian church and the Roman government not only by embracing Christianity, but also by making it a pillar of the Roman official establishment. Imperial edicts enriched the Church with privileges, favors, and public funds. Book 16 of the Theodosian Code focuses specifically on Christianity. It, for example, prohibits rebaptism, condemns apostates who left the Christian faith, and places the status of Catholics within a wider societal framework.¹³ Clerics were exempted from all compulsory public service.¹⁴ Bishops could not be summoned to civil courts; furthermore, cases involving clerics were to be heard by the bishops in ecclesiastical court.¹⁵ Every person had the right to bequeath any property he wished to the church at this death.¹⁶ The privileges granted, however, only applied to adherents of the Catholic faith. All heresies, which were addressed individually by name, were condemned: their places of worship confiscated, and their children were forbidden from inheriting.¹⁷ Paganism was banned and sacrifices condemned.¹⁸ The Roman church had become an organ of imperial government, but was also used as an arm of imperial administration.

13 Cod. Theod. 16.6 (rebaptism), 16.7 (apostates). For the contents of Book 16, see pp. 440–476. The Sirmondian Constitutions supplemented the Theodosian Code with 21 constitutions from the fourth and early fifth centuries addressing matters similar to Book 16. For more on this, see J. Matthews, Laying Down the Law: A Study of the Theodosian Code (New Haven, 2000), 121–167; and M. Vessey, “The Origins of the Collectio Sirmondiana: A New Look at the Evidence,” in The Theodosian Code: Studies in the Imperial, 2nd edn., eds. J. Harries and I. Wood (London, 2010), 178–199.14 Ibid., 16.2.2, 7, 10, 14.15 Ibid., 16.2.12, 23, 41; 16.11.16 Ibid., 16.2.4.17 Ibid., 16.5.18 Ibid., 16.10.

Yet governmental policy also served church authorities, who deemed it insufficient simply to isolate Christians from non-believers. Imperial authority made it possible to penalize Christians who rejected beliefs and practices that the church’s leaders regarded as central. As early as 380 the emperor Theodosius I described as “demented and insane” those who rejected the tenets of faith defined by the bishops of Rome and Alexandria and warned menacingly that anyone who persisted in erroneous beliefs would be subject to imperial retribution.¹⁹ In 386, Theodosius I spelled out the meaning of this last phrase more bluntly. He decreed that “authors of sedition and disturbers of the peace of the church” must “pay the penalty of high treason with their life and blood.”²⁰ Deviance from approved Christian doctrine or disobedience to the behavioral standards set by the bishops was now a capital crime. Over the course of about three generations, Christianity had been transformed from the religion of a small, persecuted minority on the fringes of Roman society into the official religion of the Roman Empire. By the century’s end, bishops had been vested with judicial authority to enforce behavioral norms, and flouting them, at least in public, was rapidly becoming hazardous to life and fortune.

19 Ibid., 16.1.2.1.20 Ibid., 16.1.4.

Roman civil law and ecclesiastical canon law would infiltrate each other’s collections and would eventually become known as utrumque ius.²¹ As will be discussed in later chapters, compilers of canonical collections of the early Middle Ages, for example, would draw directly upon Roman legal norms such as the Epitome of Julian, a work that represents a lecture course given by Julian—the best-known law professor at Constantinople—on the 124 Greek Novellae of Justinian.²² The Breviarium Alarici, also known as the Lex Romana Visigothorum, was a collection of various Roman legal texts published and compiled at the request of Alaric II, king of the Visigoths (484–507), in 506.²³ The included interpretationes (interpretations)—detailed comments on the laws that served as aides for using the law—sought to expound, summarize, give the meanings of terms, or offer updates to reflect the regional, political, social, and cultural differences in a post-Roman world that continued to use Roman law.²⁴ The Breviarium Alarici would become instrumental for canonical collections of the early Middle Ages. Compilers and users of law would not draw specifically on the Theodosian Code, rather it would be known and used through the Breviary of Alaric.²⁵

21 Ferme and Falchi, Introduzione allo studio delle fonti dell’Utrumque Iuris, ch. 5.22 S. Corcoran, “UCL Volterra Project,” https://www.ucl.ac.uk/volterra/texts/epitome-iuliani. Its use in teaching at Constantinople may not have extended far past Justinian’s death as Justin II closed the law school.23 The collection included selections from: the Gregorian Code (290s); the Hermogenian Code (290s); the Theodosian Code; Novellae (new laws) of Emperors Theodosius II (402–450) and Valentinian III (425–455) issued after the circulation of the Theodosian Code; and extracts from the Roman jurists, Papinian, Paul’s Sentences, and Gaius’ Institutes.24 J. Matthews, “Interpreting the Interpretationes of the Breviarium,” in Law, Society, and Authority in Late Antiquity, ed. Mathisen, 11–32.25 I. Wood, “The Code in Merovingian Gaul,” and D. Walters, “From Benedict to Gratian: The Code in Medieval Ecclesiastical Authors,” in The Theodosian Code, eds. Harries and Wood, 161–177 and 200–216, respectively.

Collectively, religious and imperial texts defined both norms for the religious life of members of early Christian communities and the key elements of mainstream Christian doctrine. They drew increasingly sharp lines between authentic Christians and others, whom they labelled heretics, apostates, and unbelievers. In addition, canon law in the early Church sought to enumerate the powers and qualifications of bishops and other clerics, to define their obligations, and to provide disciplinary measures to curb those who exceeded their authority or failed to measure up to the high standards of conduct expected. As Christian communities after Constantine’s time soon became large property holders, the canons also prescribed rules for the management and use of the church’s physical goods. Early canonical collections included material on a wide variety of practical issues that concerned the leaders of Christian communities. Marriage and family law, Christian attitudes toward slavery, military service, economic activities, relations between Christians and their non-Christian neighbors, and the preservation of beliefs and practices that church authorities regarded as essential all ranked at the top of the list of problems they addressed.

These texts were very much concerned with regulating marriage and family relationships, a topic already evident in the letters of St. Paul, and subsequent writers about the rules governing Christian life almost invariably dealt with it.²⁶ Christian subjects of the Roman Empire contracted marriage in much the same way as other Romans did, although from quite an early period they supplemented the observances customary among pagans with Christian rituals and blessings. Christian communities, however, conceived of the nature and consequences of marriage in quite different terms than their pagan contemporaries. Christians, for one thing, strongly discouraged marriage across religious lines and imposed sanctions, often quite severe ones, upon those who sought to marry adherents of other religions. For another, Christian law came to interpret matrimonial consent rather differently than did civil marriage law. Most Christian teachers believed that consent to marriage involved a permanent commitment that, once given, could not subsequently be revoked; pagan Roman lawyers, however, conceived of marital consent as an ongoing process, and marriage continued, in consequence, so long as the parties continued to consent to the union, but terminated once one party withdrew consent. Like contemporary pagan law, early Christian law required that parents, as well as the parties, consent to a prospective marriage; unlike pagans, however, Christians did not reserve the right of consent solely to the male head of household, but rather expected that couples should seek the agreement of all those charged with the care and supervision of the young before entering into a marital union.²⁷

26 For example, I Cor. 7:1–9, 26–36; Eph. 5:3–4; Gal. 5:16–21.27 S. Treggiari, Roman Marriage: Iusti coniuges from the Time of Cicero to the Time of Ulpian (Oxford, 1991); J. Gaudemet, L’èglise dans l’empire romain (IVe–Ve siècles), Vol. 3: Histoire du droit et des institutiones de l’èglise en Occident (Paris, 1989), 515–554.

Christian law concerning slavery also departed in important ways from the norms common among pagan Romans. No Christian authorities condemned the practice of slavery outright, to be sure; they commonly accepted the institution as a necessary and inevitable social institution. It was not unusual for Christian churches and the clergy, as well as laymen, to possess slaves of their own and to employ them to perform the many kinds of routine labor for which the technology of late antiquity provided no satisfactory alternative energy sources. At the same time, however, Christian religious teachers, like some of their pagan counterparts, particularly among the Stoics, affirmed that slavery was unnatural, and that in an ideal world all human beings ought to be free. Since this present terrestrial world was far from ideal, however, both the law and the practice of early Christian communities sought to limit the exploitation of slaves, rather than to abolish an institution so central to the society and economy of their age. Christian law, although it did not attack the institution of slavery, did insist that Christians must treat their slaves humanely and admonished owners to make every effort to provide for the religious needs of their slaves. The canons, unlike Roman civil law, recognized the capacity of slaves to marry legitimately and attempted to preserve the integrity of slave families by restricting the rights of owners to separate married slaves from their spouses and children.²⁸

28 M. Sommar, The Slaves of the Churches: A History (Oxford, 2020); Gaudemet, L’èglise dans l’empire romain (IVe–Ve siècles), 563–567; M. Falcão, Las prohibiciones matrimoniales de carácter social en el Imperio Romano (Pamplona, 1973).

The texts of the early Church were also concerned with issues involving military service and, more generally, the restrictions that Christian society ought to place on violence. The question of whether Christians could serve in the Roman army troubled several early Church Fathers, as did related questions about the circumstances under which it was proper for a Christian to use force to defend himself, his family, or his community from aggressors. During the period of religious persecution prior to Constantine, Christians debated whether it was lawful for them to resist the persecutors, while after Constantine the focus shifted to questions about the circumstances under which a Christian government might wage war and whether Christians should participate in the execution of criminals condemned by Roman courts.²⁹

29 A. von Harnack, Militia Christi: The Christian Religion and the Military in the First Three Centuries, trans. D. McInnes Gracie (Philadelphia, 1981); L. Swift, “Search the Scriptures: Patristic Exegesis and the Ius belli,” in Peace in a Nuclear Age, ed. C. Reid, Jr. (Washington, DC, 1986), 34–68.

Church authorities in the Christian Empire became increasingly anxious to insulate members of their flock from Jews and pagans who remained outside the fold. Hence canon law showed growing concern during the fifth and sixth centuries about limiting even casual contacts with unbelievers. Canons of councils and local synods forbade the faithful to dine with non-Christians, to dance with them, or to share the baths with them, much less to participate, even passively, in circumcisions and other non-Christian religious observances. Christians were not to accept the care of Jewish physicians or to call Jews as witnesses in lawsuits. No pagan or Jew was to exercise authority over Christians as a judge or magistrate, and non-Christians were restrained from buying or keeping Christian slaves. Christian parents, moreover, were encouraged to see to it that their children were taught exclusively by Christian teachers. Christian teachers, in turn, were warned repeatedly to beware of the harmful consequences of having their pupils study pagan literature and philosophy save under strict supervision, lest they imbibe ideas and attitudes that might inhibit proper spiritual development. All of these restrictions on contacts between Christians and those who did not share their religious beliefs sought in part to preserve religious orthodoxy from contamination by alien beliefs and ideas and also to foster the dissemination of Christian beliefs and ideas among the faithful.

Norms that regulated Christian monasticism, which first appeared during the third century in the eastern Mediterranean (above all in Egypt and Syria), would complement the canonical tradition. Monks and nuns lived under a regula, or rule, that comprised of teachings of the original founder, guidelines to practical application of Scripture, guidelines for beginners entering the monastic life, tools to exercise humility, particular regulations for the community, punishments for various transgressions, and the formal and legal basis for monastic conversion. About thirty rules survive from the Latin West dating from late antiquity to the mid-sixth century. While there was no one “standard” rule for all monks and nuns, they all embraced the Bible as the ultimate source. Each rule sought to guide the shape, and regulate every aspect, of communal (cenobitic) monastic life. For example, rules covered such topics as liturgical hours, dress, diet, visitors, and engaging with the outside world.³⁰ Among the more prevalent rules from the first quarter of the fifth century (ca. 400–425) were the Rule of Pachomius,³¹ the Rule of Basil,³² and Augustine’s Praeceptum and the Ordo monasterii likewise attributed to him.³³ In the sixth century, influential rules were those of Caesarius (d. 542) for nuns,³⁴ and, in particular, the anonymous Rule of the Master (Regula magistri, before 530) which St. Benedict of Nursia used as a source to compile his Rule (ca. 550).³⁵ Benedict’s Rule prescribed a balanced regimen in which the monk’s daily routine centered on periods of formal community worship, physical labor, and individual meditation and prayer. Each monastic house, which sought to be a self-sufficient agricultural community isolated so far as possible from contact with worldly society, constituted an autonomous, self-governing community, headed by an abbot whom the monks elected for life. Under the abbot, and responsible to him, subordinate officials bore responsibility for organizing and managing the spiritual and material resources of the group. As monks, nuns, and hermits emerged in the West in the mid-fourth century and as monasticism became an increasingly prominent feature of Christian religious life and practice, particularly from the fifth and sixth centuries onward, canon law would have to take account of their status and the status of their property.

30 A. Diem, “Monastic Rules,” and H. Feiss, OSB, “Benedict’s Rule,” in Great Christian Jurists and Legal Collections in the First Millennium, ed. Reynolds, 214–236, here 230–231, and 334–352, here 336, respectively. For a particularly helpful introduction to monasticism in general, see G. Melville, The World of Medieval Monasticism: Its History and Forms of Life (Collegeville, 2016). For more information on historiographical trends in the field of medieval monasticism, see the essays in A. Beach and I. Cochelin, eds., Cambridge History of Medieval Monasticism (Cambridge, 2020).31 P. Rousseau, Pachomius: The Making of a Community in Fourth-Century Egypt (Berkeley, 1999), esp. 77–104.32 A. Silvas, trans., The Rule of St Basil in Latin and English: A Revised Critical Edition (Collegeville, 2013).33 T. van Bavel, ed., and R. Canning, trans., The Rule of Saint Augustine (Kalamazoo, 1996).34 M. McCarthy, trans., The Rule for Nuns of St. Caesarius of Arles: A Translation with a Critical Introduction (Washington, DC, 1960).35 A. de Vogüé, Études sur la Règle de Saint Benoît: Nouveau recueil (Bégrolles-en-Mauges, 1996).

Canon law grew out of norms stemming from the Bible, from Church Fathers, from councils and synods, from papal decretals, and from monastic rules that, collectively, served as mechanisms for regulating religious beliefs and practices. The Christian church of late antiquity and the early Middle Ages, however, would become more legalistic, particularly as Roman law addressed matters of faith. As the organization of the church transformed and norms, as we will see, were gathered into canonical collections to be used by ecclesiastical officials, canon law would emerge as not only an important element of Christian religious life, but also as an autonomous legal system complementary to the legal system of late Roman government.