Church History — Unit 5: Medieval Christianity

Unit 4 ended with Augustine dying in 430 as the Vandals besieged Hippo. Unit 5 picks up the story and carries it eight hundred years — through the collapse of the Roman political order, the rise of Islam, the slow building of a new Christian civilization on the rubble of the empire, the parting of East and West, the Crusades, the great medieval reform movements, and the rise of scholastic theology. By the year 1300 the church will have produced cathedrals, universities, hospitals, and Aquinas's Summa Theologica. By 1300 she will also have accumulated the corruptions and contradictions that produce the storm of Unit 6.

Eight hundred years is too much for one unit. We will move at altitude and stop only at landmarks. Gregory the Great (the medieval papacy), the rise of Islam, Charlemagne, the Great Schism of 1054, the Crusades, monastic reforms, and scholastic theology. And underneath all of it, a thread we have not yet named explicitly — the thread of the suffering church. Constantine ended the Roman persecution in 313, but the suffering of God's people did not end with Constantine. It moved. It changed shape. It crossed borders. But it never stopped. From Vikings to Mongols to plagues to the long, varied experience of the ancient eastern churches under Islamic rule — sometimes marked by real toleration and intellectual exchange, sometimes by restriction and severe persecution, and never simply erased — the medieval centuries are full of believers who walked exactly where Peter said all believers walk: in the footsteps of a suffering Lord.

The first great medieval pope was Gregory I, called Gregory the Great, who held the see of Rome from 590 to 604. He was born into a noble Roman family, sold his property, founded seven monasteries, became a Benedictine monk, and was reluctantly elected pope at fifty.

The Rome Gregory inherited was a ruined city. The Western Empire had been gone for a century. Plague, famine, and Lombard invasions had emptied the population. Gregory, almost by default, found himself running not just the church but the city — negotiating with the Lombards, feeding the poor, organizing relief, providing the kind of stable government the empire could no longer supply. The bishop of Rome would now be not just the spiritual head of the Western church but a temporal lord with political responsibilities. The medieval papacy was being born.

Gregory was also a pastor and writer of the first rank. His Pastoral Rule (Regula Pastoralis) was the most-read manual of pastoral ministry in the Western church for the next thousand years — how to balance contemplation and action, how to preach to different kinds of hearers, how to discipline without crushing, how to comfort without flattering. Charlemagne later required every bishop in his empire to own a copy.

Gregory called himself servus servorum Dei — "servant of the servants of God." Every pope after him has used the title. The man who effectively founded the political papacy gave it a self-description borrowed from the basin where Jesus washed the disciples' feet. The medieval papacy that grew up after Gregory would not always live up to that self-description, but the title remained as a permanent rebuke whenever the office forgot what it was. Gregory also sent missionary bishop Augustine of Canterbury (not Augustine of Hippo) to England in 597. Within a generation the Anglo-Saxons had been converted.

In 622, an Arabian merchant named Muhammad fled from Mecca to Medina — the hijra, the foundation date of the Islamic calendar. Within twenty years of his death in 632, Muslim armies had conquered Syria, Palestine (Jerusalem fell in 638), Egypt, and were sweeping across North Africa. By 711 they crossed into Spain. By 732 they were stopped at the Battle of Tours by the Frankish leader Charles Martel. The map of the Christian world had been redrawn forever.

The losses were catastrophic. The North African church of Tertullian, Cyprian, and Augustine essentially disappeared. The Egyptian church of Athanasius and Cyril was reduced to a Coptic minority. The Syrian and Palestinian churches lost their majority status. The patriarchates of Alexandria, Antioch, and Jerusalem — three of the five great sees of the ancient church — survived but as minorities under Muslim rule. The cradle lands of Christianity were no longer Christian-majority. They have not been Christian-majority for fourteen hundred years. Yet survived is the right word: these ancient communities were not erased. Their experience under Muslim rule varied enormously across the centuries and regions — periods of real toleration in which Christian scholars helped translate Greek learning into Arabic and served in courts and professions, alongside periods of heavy taxation, social restriction, and at times severe persecution. Coptic, Syriac, Armenian, and other ancient churches survive in the Middle East and North Africa to this day, an unbroken thread reaching back to the apostolic age.

The Eastern Roman Empire (Byzantium), centered on Constantinople, held Asia Minor and the Balkans for another eight hundred years, but it was now smaller, more Greek, more besieged. Western Christendom, cut off from the southern Mediterranean, became increasingly Latin and increasingly oriented around the Frankish kingdoms north of the Alps. The center of gravity of Christianity moved north for the first time in its history.

The Frankish kingdom that Clovis had baptized in 496 grew in power for two centuries. Its greatest king was Charlemagne (Charles the Great, 768–814). Charlemagne unified most of Western Europe under one rule for the first time since the fall of Rome. He fought wars against the pagan Saxons in Germany and the Muslim Moors in Spain. He sponsored a major intellectual revival, the Carolingian Renaissance: importing scholars like the Englishman Alcuin, founding palace schools, ordering the careful copying of Latin manuscripts (the script we still call Carolingian minuscule was developed under his patronage). He standardized the liturgy and reformed the clergy.

The high political moment came on Christmas Day in the year 800, in St. Peter's Basilica in Rome. Pope Leo III crowned Charlemagne Imperator Romanorum — "Emperor of the Romans." A Christian Roman emperor in the West, for the first time since 476. The crowning was the founding act of what would later be called the Holy Roman Empire, a political-religious construct that would last in some form until 1806.

Charlemagne's legacy is mixed. On one side: literacy preserved, Scripture copied, monasteries protected, missions launched into pagan Europe, a continental Christian civilization restarted. On the other side: forced conversions of Saxons under threat of execution, the entanglement of throne and altar that would compromise both for the next thousand years, the assumption that political power was a proper instrument of Christian mission. Charlemagne baptized Saxons at sword-point and founded universities by imperial decree. The medieval Christendom we are about to walk through is built on both halves of his work.

Christianity had grown up with two cultural centers. The Greek-speaking East — Constantinople, Antioch, Alexandria, Jerusalem — produced the great theological controversies of the patristic era. The Latin-speaking West — Rome, North Africa, Spain, Gaul — produced Augustine, Jerome, and the early medieval papacy. For a thousand years they had been one church.

The drift began long before 1054. East and West used different liturgies, different languages, different breads in the Eucharist (Greek leavened, Latin unleavened), different rules for clergy marriage. Most consequentially, they disagreed about the procession of the Holy Spirit. The original Nicene-Constantinopolitan Creed of 381 said the Spirit "proceeds from the Father." Western churches added "and the Son" — in Latin, filioque. The East considered the addition theologically wrong and procedurally illegitimate.

The growing tension came to a head over papal authority. The bishop of Rome claimed primacy over all Christian bishops. The patriarch of Constantinople recognized Rome as first among equals but rejected universal jurisdiction. In July 1054 a papal delegation led by Cardinal Humbert marched into the Hagia Sophia in Constantinople during the divine liturgy, laid a bull of excommunication on the altar, and walked out. The patriarch Michael Cerularius excommunicated the legates in turn. The Latin West and the Greek East have been formally separated ever since. The mutual excommunications were finally lifted in 1965 by Pope Paul VI and Patriarch Athenagoras, but the structural separation remains. The two halves of the ancient church have not celebrated the Eucharist together for nine hundred and seventy-two years.

In 1095 at the Council of Clermont in southern France, Pope Urban II preached a sermon that launched two centuries of armed pilgrimage to the Holy Land. The Byzantine emperor had asked Western help against the Seljuk Turks. Urban responded with a vision both larger and more dangerous: a great expedition of Western Christian warriors to recover the holy places of Palestine from Muslim rule. The crowd shouted back "Deus vult!" — "God wills it!" — and the First Crusade was born.

The First Crusade (1095–1099) actually succeeded. Crusader armies crossed Asia Minor, captured Antioch, and in July 1099 took Jerusalem itself, slaughtering the city's Muslim and Jewish inhabitants in a massacre that has scarred Christian-Muslim relations ever since. A series of Crusader states was established along the eastern Mediterranean coast. They lasted in fragments until the fall of Acre in 1291, almost two centuries.

The eight or so subsequent Crusades were less successful and increasingly compromised. The Second Crusade (1147–1149), preached by Bernard of Clairvaux, failed. The Third Crusade (1189–1192), led by Richard the Lionheart, recovered some coastal cities but not Jerusalem. The Fourth Crusade (1202–1204) sacked Constantinople — the capital of the Eastern Christian empire it was supposed to be helping. Eastern Christianity has never forgiven that betrayal. The Children's Crusade of 1212 ended in disaster, with most of the children either dying or being sold into slavery in Egyptian ports. By 1291 the Crusader states were gone and the Holy Land was permanently in Muslim hands.

What should the modern Christian make of the Crusades? Three things at least. First, the Crusades represent a category confusion that runs deep in medieval Christendom: the assumption that Christ's kingdom advances by the sword. The early church had never thought so. The post-Constantinian church increasingly did. By the time of Urban II, military pilgrimage was being preached as a meritorious act of penance. The category confusion is not the gospel; it is a cultural assumption Christians too readily absorbed. Second, the Crusades did real harm: the slaughter at Jerusalem in 1099, the sack of Constantinople in 1204, the Jewish pogroms preached up by some Crusade recruiters in the Rhineland. These are sins of the church, not victories. Third, the Crusades did some unintended good: revived contact with Greek and Arab learning, opened trade routes that fueled the later Renaissance, and forced Western Christians to recognize that Christianity was bigger than Latin Christendom. But the moral ledger is heavily negative. The pastor who studies the Crusades faithfully will preach "my kingdom is not of this world" (John 18:36) with sharper conviction.

The medieval church repeatedly produced movements of internal reform when she drifted from her own ideals. Three reform waves stand out.

Cluny was a Benedictine monastery founded in 910 in Burgundy. Its founders insisted on a strict observance of the Benedictine rule, on freedom from local lay control, and on direct accountability only to the pope. Cluny became the head of a network of reformed monasteries that eventually numbered in the thousands. The Cluniac reformers cleaned up clerical corruption, fought against the practice of selling church offices (simony) and against married clergy, and produced one of the most powerful popes of the Middle Ages: Gregory VII (Hildebrand), pope from 1073 to 1085, who in the Investiture Controversy forced Emperor Henry IV to wait three days barefoot in the snow at Canossa for absolution.

The Cistercians, founded in 1098, were a still stricter Benedictine reform. They wanted manual labor, simple chapels, plain liturgy, and remote locations. Their most famous member was Bernard of Clairvaux (1090–1153), one of the most influential preachers and spiritual writers of the Middle Ages. Bernard preached the Second Crusade, mediated papal disputes, advised kings, and wrote sermons on the Song of Songs that are still in print. He combined a tender Christ-centered piety with a steel will. Luther later said Bernard was the best man of the Catholic Middle Ages, the one whose sermons he could most cheerfully recommend.

The friars were a thirteenth-century reform of an entirely different shape. Francis of Assisi (c. 1182–1226), the son of a wealthy Italian cloth merchant, heard Matthew 10 read in church one morning and took it as a personal command: leave everything, take nothing for the journey, preach the kingdom and heal the sick. He stripped naked in the town square, returned all his clothes to his furious father, and began a life of literal apostolic poverty. His followers — the Franciscans — were not cloistered monks but wandering preachers who begged their bread and brought the gospel into the towns and markets. Around the same time the Spaniard Dominic (c. 1170–1221) founded the Dominicans (the Order of Preachers), a parallel mendicant order specifically focused on preaching against heresy. Both orders combined poverty, preaching, education, and direct submission to the pope. Both produced theological giants — the Franciscans gave the church Bonaventure, the Dominicans gave her Aquinas. The friars revived popular preaching in a Western church that had increasingly let the sermon slide. They are the medieval forerunners of the recovery of preaching that would peak in the Reformation of Unit 7.

The same centuries that produced the friars also produced the medieval universities — Bologna, Paris, Oxford, Cambridge. The new universities gave Western Christianity a kind of intellectual seriousness that had not existed since the patristic era. The theology done in them is called scholastic, from the Latin schola, the school. Two figures stand out.

Anselm of Canterbury (1033–1109) was an Italian-born Benedictine monk who became Archbishop of Canterbury. He gave the church the famous formula "faith seeking understanding" (fides quaerens intellectum) — theology is not skepticism trying to talk itself into belief, but trust trying to understand what it already trusts. His Proslogion contains the ontological argument for God's existence (the most discussed and disputed argument in philosophy ever since). His Cur Deus Homo ("Why God Became Man") gave the church the satisfaction theory of the atonement: only God could satisfy what God's justice required, and only a man could pay what humanity owed, so the Mediator had to be the God-man Jesus Christ. The satisfaction framework would later shape the Reformers' penal substitution theology.

Thomas Aquinas (1225–1274) is the towering theologian of the Middle Ages. A young Italian noble, he was kidnapped by his family to keep him from joining the new Dominican order; he escaped, took the habit, studied at Paris, and devoted his life to massive theological synthesis. His Summa Theologica, written for beginners (his words), runs to about three and a half million words and is one of the supreme intellectual achievements of the Western mind. Aquinas baptized the philosophy of Aristotle for Christian use, defended the harmony of faith and reason, articulated the famous Five Ways of arguing for God's existence, and produced a systematic theology of grace, sacraments, virtues, and law that has shaped Roman Catholic theology ever since. He died at forty-nine on his way to a council, after telling his secretary that everything he had written seemed to him "like straw" compared to what he had seen in a vision a few months earlier.

Scholasticism's strengths and weaknesses both run deep. Strength: it taught Western Christianity to think with discipline, to distinguish carefully, to argue rigorously. Weakness: it gradually let philosophical scaffolding obscure the simplicity of the gospel, and by the late Middle Ages had produced a system in which justification by grace through faith was buried under technical precision. The Reformers of Unit 7 will react against scholasticism even while inheriting some of its tools.

First, the Promise of Matthew 16:18 is bigger than any one century's circumstances. The medieval church watched her ancient eastern half disappear under Islam, her monasteries burn under Vikings, her communities die under plague, and her Eastern missions perish under Mongols. None of these losses broke the Promise. They redrew its map. The pastor who measures the church's health by his own century's headlines has not yet learned what 1 Peter and Matthew 16 were trying to teach.

Second, suffering is not failure. The Coptic, Syriac, and Armenian churches enduring fourteen centuries of dhimmi status are not stories of the church losing. They are stories of the church being conformed to her Lord. American Christians, who have known three centuries of unusual safety, will grow into a more biblical understanding of the church when they begin to see suffering as the Christian norm rather than the Christian exception.

Third, the church corrects herself when she stays under the Word. Cluny corrected lazy monasticism. The Cistercians corrected wealthy monasticism. Francis corrected acquisitive monasticism. The friars corrected silent pulpits. Anselm and Aquinas corrected unthinking faith. The Reformation of Unit 7 will correct everything they did not. The church's capacity for self-correction is not a Reformation invention; it has been operating in every century since Pentecost. Pastor, expect God to keep correcting your church too.

Fourth, beware the sword. The Crusades are the great medieval warning. When the church takes up worldly power as a tool of mission, she compromises the gospel and harms her witness. "My kingdom is not of this world" (John 18:36). Whatever your political moment looks like, do not let the church confuse her weapons with the world's.

By 1300 the medieval Christian West had reached its high water mark. Aquinas had finished the Summa and gone home. Notre Dame de Paris was finished. The friars were preaching in every market square. The popes were at the height of their political power. Boniface VIII would issue the bull Unam Sanctam in 1302 declaring that submission to the pope was necessary for every human being's salvation.

And then the cracks. Boniface himself was attacked and humiliated by agents of the French king the next year and died of the shock. The papacy moved to Avignon under French control for seventy years. The Black Death struck. The Hundred Years' War devastated France. By 1378 there were two popes simultaneously, then three. Reformers like Wycliffe and Hus began calling for return to Scripture. The medieval synthesis was about to come apart. Pass this examination, and we will meet the storms of the late Middle Ages in Unit 6 — the storms that will produce the Reformation.