Byzantine Religion and the Orthodox Church

Religion was the central, defining institution of the Byzantine Empire. Every emperor was crowned by the Patriarch of Constantinople in the great church of Hagia Sophia. Every imperial edict opened with an invocation of the Holy Trinity. Every civic ceremony, every military campaign, every new law was framed as a Christian act performed by a Christian emperor under the guidance of the Christian God. The Orthodox Church was not a department of the state, but neither was it a separate institution: it was the religious dimension of the Roman state, and the emperor’s role as defender of the faith was as essential to his office as his role as commander of the army or author of laws.

The argument below links forward to the iconoclasm controversy, to the related question of why iconoclasm happened in the Byzantine Empire, and to the broader treatment of the Byzantine church.

Constantinople and the Patriarchate

The bishop of Constantinople, known from the late fourth century as the Patriarch of Constantinople, was the senior ecclesiastical figure of the eastern empire. The patriarchate had been founded, in effect, with the city’s dedication in 330; the Second Ecumenical Council of 381 gave the bishop of Constantinople honorary primacy over the eastern churches second only to the bishop of Rome. The patriarch’s jurisdiction extended over the bishops of Asia Minor, the Balkans, and the Aegean islands, and through missionary activity it came to include the newly Christianized peoples of Bulgaria, Serbia, Rus’, and other Slavic lands.

The patriarch’s authority was exercised in cooperation with the emperor. The emperor appointed the patriarch, who was usually drawn from the clergy of the Great Church; the patriarch crowned the emperor; both were understood to share responsibility for the unity of the Church and the orthodoxy of doctrine. The most serious disputes between patriarchs and emperors were over the limits of imperial authority in religious matters, and the resulting conflicts (over iconoclasm, over the union of the churches with Rome, over the appointment of bishops) formed the recurring crises of Byzantine religious life.

The Ecumenical Councils

The doctrinal foundations of the Orthodox Church were defined in the seven Ecumenical Councils, of which all but the first were held in the eastern Roman Empire and presided over by the emperor or his representative. The First Council of Nicaea, in 325, formulated the Nicene Creed against Arianism. The First Council of Constantinople, in 381, completed the creed with the articles concerning the Holy Spirit. The Council of Ephesus, in 431, defined the unity of Christ’s person in opposition to Nestorianism. The Council of Chalcedon, in 451, defined the two natures of Christ against Monophysitism.

The Chalcedonian definition, however, provoked the lasting schism of the Monophysite churches, which included the Coptic Church of Egypt, the Syrian Orthodox Church, the Armenian Apostolic Church, and the Ethiopian Church. The Monophysites believed that Christ’s divine and human natures were united in a single, primarily divine nature; Chalcedon’s two-natures formula seemed to them Nestorian in disguise. Justinian’s attempts to resolve the controversy by force of imperial authority failed, and the schism endured throughout the Byzantine period, weakening the empire in the very provinces (Egypt, Syria, Armenia) that were the first to fall to the Arab conquests. The emperor’s role in religious councils is examined in the Emperor Justinian and his reign, particularly in connection with the Fifth Council and the Three Chapters controversy.

Liturgy and Worship

The Orthodox liturgy, in its Byzantine form, was one of the great cultural achievements of the early Middle Ages. The Divine Liturgy of St. John Chrysostom, in its mature ninth-century form, was a complex synthesis of prayer, scripture, psalmody, and chant performed in the great cathedral of Hagia Sophia and in the parish churches of Constantinople and the provinces. The cathedral liturgy, with its procession of the deacons, the chanting of the choir, the iconography of the sanctuary screen, the use of incense, and the moment of consecration, was a theatrical and theological event of the highest order.

The liturgical life of the Church was governed by a calendar of fixed feasts (Christmas, Epiphany, the Annunciation, the Dormition of the Virgin, the feast of the patron saint of a particular church) and movable feasts tied to the date of Easter. The Great Lent fast and the paschal celebration were the central religious events of the year. The faithful received communion in both kinds (bread and wine), the bread being leavened in contrast to the Latin practice of unleavened wafers; this difference, along with several others, became a point of dispute with the Latin west.

The musical and architectural settings of the liturgy were integral to its meaning. The great cathedral of the Hagia Sophia, with its vast central dome and its golden mosaics, was the supreme example; but the same essential arrangement — apse, sanctuary, nave, and narthex — was reproduced in churches across the empire. The use of icons, which depicts Christ, the Virgin, the saints, and the angels in a stylized, frontal, hierarchical form, was an integral part of Orthodox worship and a major point of dispute with the iconoclasts.

Monasticism

Monasticism flourished in the Byzantine Empire. The great deserts of Egypt, Palestine, and Sinai were the cradle of Christian monasticism, with St. Anthony the Great, St. Pachomius, and St. Basil the Great establishing the eremitic and cenobitic traditions in the fourth century. St. Basil’s Rule, more austere than the Benedictine rule that would develop in the west a century later, became the standard rule for Greek-speaking monasticism. The tradition of Byzantine monasticism is treated in more detail in monasticism and the Benedictine rule.

By the ninth and tenth centuries, monasticism in the Byzantine Empire had been substantially reformed under the influence of the Studite reform, led by Theodore the Studite (759–826) at the monastery of St. John the Baptist in Constantinople. The Studite rule, more rigorous in discipline and more careful in liturgical practice than earlier forms of Byzantine monasticism, became the standard rule for Orthodox monasteries. Monasticism produced some of the empire’s greatest theologians, hymnographers, and chroniclers; among them, John of Damascus and Theodore the Studite were both defenders of the veneration of icons during the iconoclast period. The complementary development of Orthodox monasticism in the Latin west is treated in monasticism and the Benedictine rule.

The Iconoclast Controversy

The most divisive religious controversy of the early Middle Ages was iconoclasm, the imperial prohibition of religious images that began under the emperor Leo III in 726 and lasted, with interruptions, until 843. The iconoclasts argued that the veneration of icons was idolatry forbidden by the Old Testament; the iconodules (defenders of icons) argued that the veneration paid to icons was a relative veneration passing through the image to the prototype (Christ, the Virgin, the saint) it depicted.

The controversy was not purely theological. It had political dimensions (the army, the rural bishops of Anatolia, and the iconoclast emperors were often on the same side; the monks, the civil aristocracy, and the iconodules were often on the other) and cultural dimensions (the destruction of icons, the loss of much religious art, and the eventual restoration of the icon tradition under the empress Theodora in 843). The controversy is treated in more detail in why iconoclasm happened in the Byzantine Empire and in iconoclasm controversy in early medieval Christianity.

It is worth flagging that the older, largely political reading of the controversy (iconoclasm as a campaign to strip wealth from the monasteries) has been seriously challenged by Leslie Brubaker and John Haldon in Byzantium in the Iconoclast Era (2011). On their account the iconoclast position was a coherent theological and pastoral programme, not a front for confiscation, and the conflict was a genuine dispute about representation that cannot be reduced to court politics.

The Second Council of Nicaea, convened in 787 by the iconodule empress Irene, condemned iconoclasm and defined the orthodox doctrine of icons. A second iconoclast period from 815 to 843 followed, and the final restoration of the icons in 843, known as the Triumph of Orthodoxy, is still celebrated by the Orthodox Church on the first Sunday of Lent. The theological legacy of the controversy, the practice of icon veneration, is one of the central features of Orthodox Christianity.

Missions and the Conversion of the Slavs

Byzantine Christianity was not confined to the empire. In the ninth century, the great mission to the Slavic world, led by the Cyril and Methodius, translated the liturgy and the scriptures into Old Church Slavonic and laid the foundations of Slavic Christian culture. The mission was at first directed at Great Moravia, but political changes expelled the brothers from the principality, and the disciples of Cyril and Methodius were welcomed in the First Bulgarian Empire, where they founded the Bulgarian literary tradition.

The conversion of the Bulgars, the Serbs, and the Rus’ brought the Orthodox faith and the Byzantine cultural inheritance to a vast region of eastern Europe. The conversion of the Rus’ in 988, accomplished under the Byzantine political pressure of the emperor Basil II, made Kyivan Rus’ an important Orthodox state. The churches of the Rus’ — the great cathedrals of Kiev, Novgorod, and Vladimir — were built in the Byzantine style and decorated with Byzantine icons; the icon painting of Novgorod and Moscow was, in later centuries, one of the great continuations of the Byzantine tradition.

Relations with Rome

The relationship between the patriarchate of Constantinople and the papacy was, from the fifth century onward, the central ecclesiastical question of the medieval Mediterranean. The bishop of Rome claimed universal jurisdiction over the Christian church on the basis of the apostolic foundation of the city; the patriarch of Constantinople claimed seniority on the basis of the imperial foundation of the city and the dignity of being the senior bishop of the eastern Roman Empire. The two thrones had been in intermittent conflict from the time of the Acacian schism (484–519), and the tension only deepened over the centuries.

The Photian schism of 863–867, in which Pope Nicholas I excommunicated Patriarch Photius, was a major early medieval crisis; the question of whether Bulgaria belonged to the Latin or the Greek ecclesiastical jurisdiction was the immediate cause. The schism of 1054, in which Cardinal Humbert of Silva Candida and Patriarch Michael Cerularius exchanged mutual excommunications, is the conventional date for the formal separation of the Eastern and Western churches, although the underlying tensions were much older. The relationship between the two thrones, and the long-standing tension between Roman and Byzantine Christianity, is also addressed in the Pope Gregory the Great and the papacy in the early Middle Ages.

Legacy

Byzantine Christianity shaped the medieval world. From the Balkans to the Caucasus, from Kyivan Rus’ to Ethiopia, the Orthodox tradition of the Byzantine church preserved the liturgy, the theology, the canon law, and the artistic heritage of the early Christian Roman Empire. The Orthodox Church, even after the empire’s political collapse, remained a living institution, and its theology, its canon law, and its liturgy continued to shape the Christian east for centuries.