The Church in the Middle Ages: The Emergence of Roman Catholicism and Eastern Orthodoxy

While there were differences between churches in various towns and regions from the earliest days of the church, the Middle Ages saw the development of two distinct traditions or trajectories in terms of the church in the West and in the East, with the West reflecting Roman Catholicism (from which Protestantism would later emerge...we’ll get to that movement later) and Eastern Orthodoxy. I will attempt to sketch the development of these two branches in the Middle Ages, recognizing that I write not being part of either tradition, and thus will try to offer an account from my study of church history.

Rise of Rome

It seems that shortly after the apostolic period, bishops started to emerge. These bishops would oversee the churches led by elders in a particular area and offer guidance and support. For example, the church in Alexandria had 12 elders ruling all the way to the third century with one of the elders among them being elected to bishop. Bishops of various places would interact as well as equals, with some key locations being Jerusalem, Ephesus, Antioch, Corinth, and Rome. At times there was a special status given to the bishop of Rome in light of the city’s connections to Peter and Paul, the importance of Paul’s letter to the Romans, and Rome’s status as the capital of the empire; the destruction of Jerusalem may also have helped make Rome more prominent. However, it did not seem this bishop had a higher authority; one could say that the view was closer to that of it being “first among equals” rather than having more authority than others. In fact, there were situations in which other church leaders such as Cyprian or Irenaeus criticized the decisions of the bishop of Rome, and the bishop of Rome did not play any role in the Council of Nicea.

Over time, however, things seemed to shift. At the Council of Sardica (343), the bishop of Rome was given the right to hear appeals of other bishops. The Council of Constantinople in 381 also affirmed Rome’s primacy of jurisdiction but added that the bishop of Constantinople was second because Constantinople was the new Rome. Even more than these councils were the circumstances of the time that led to Rome taking a stronger leadership in the church. Leo the Great was bishop of Rome from 440-461 and he was a strong leader whose ideas were prominent in the discussions around the Council of Chalcedon. Gregory the Great (590-604) exhibited strong spiritual and political leadership during a period in which Rome was falling apart, as there were invasions of Italy. In fact, Gregory negotiated a truce with the invading generals and effectively became the chief administer of the city. These developments helped make the church in Rome the leading church in this era, moving in the mind of some from being first among equals to being over the other churches.

Tensions Between East and West

The churches in the East, however, did not have the same perspective about the bishop of Rome having more power. They believed that authority rested in councils, gatherings of bishops. Moreover, the bishop of Constantinople was called the ecumenical patriarch; he would look to the bishop of Rome as a senior but did not see him as having jurisdiction in the eastern part of the empire. There were also major patriarchs in the towns of Alexandria, Antioch, and Jerusalem. Therefore, tensions mounted as the bishop of Rome claimed more authority. 

Political factors also caused tension. Pope Leo II anointing Charlemagne as Augustus and Emperor of the West in 800 created a stir because Charlemagne would come into conflict with the Eastern Emperor. The rise of Islam caused communication to be more difficult between the two branches and the patriarch of Constantinople to have more influence and authority because other key cities (Alexandria, Antioch, Jerusalem) were under Muslim rule.

A further point of tension was tied to the Nicene Creed because at the Council of Aix (809), the Western Church added what is known as the filioque clause to the Nicene Creed to now say that we believe “in the Holy Spirit, the Lord and giver of life, who proceeds from the Father and the Son” [italics is the addition]. The intent was to confirm the equality of the persons of the Trinity, but adjusting the creed caused some concern. 

Differences Between East and West

There were also different customs and practices between the churches that developed over the years. One notable one was that the Western Church prohibited married clergy and forbid facial hair, while the East allowed priests (but not bishops) to marry and have facial hair. The West used the Latin language and typically drew on the teachings of Augustine and Tertullian, while the East spoke Greek and looked to figures like John Chrysostom, Basil of Caesarea, Gregory of Nyssa, and Gregory of Nazianzus. Other differences also existed in the practices of the church such as fasting practices and the bread used in communion.

The Final Break(s)

A variety of factors, therefore, led to there being a difference between the churches of the East and the West, but these came to a flashpoint in the 1000’s when there was a formal break. In 1053, the ecumenical patriarch, Michael Cerularius, ordered the closing of all churches in Constantinople using Latin liturgical rite (this was after Greek churches in Italy were told to conform to Latin practices or close). The next year, Pope Leo IX sent Humbert of Silva Candida to Constantinople to calm waters, with this delegate insisting on the ecumenical patriarch/bishop of Constantinople accepting Roman power (he refused). On June 16, 1054, Cardinal Humbert appeared at the Hagia Sophia, walked to the high altar, and placed a sentence of excommunication against the patriarch and those who followed him. In response, Cerularius issued a sentence of excommunication back. This is known as the Great Schism and is the reason there are Catholic and Orthodox churches. (The largest Orthodox communities are in Russia, Romania, Greece, and Constantinople.)

Later, events in the Crusades sealed this break and prevented any sort of reunion. For example, in 1204, some crusaders from the West stopped in Constantinople and pillaged the city and desecrated Hagia Sophia. For the next 1,000 years, these branches in Christianity have their own distinct history and development. In recent times, there has been more interaction between the two (for example, the letters of excommunication were lifted in 1965), but one must recognize the history that has led to these different branches.

Thinking About This Division as Part of Family Heritage

I find the model of “family heritage” helpful to understand the development of these branches of the church. Geographical and cultural factors can cause family relationships to change, as well as time; this seems to be true in the first 1,000 years of the church as the church grew in different parts of the Roman empire and developed differently. At times, there are even certain conflicts or events that can lead to tension and breaks in the family, with time and space often putting these differences into perspective. One often finds that there are different customs and practices among one’s cousins, and this becomes even more true as you look to distant relatives. 

The Roman Catholic and Eastern Orthodox churches developed in their own ways over the first 1,000 years in their history and have their own history for the past 1,000 years. In order to understand their branches, one needs to understand how they came about as well as how they have developed since. Hopefully this overview helps our understanding of their origins in the Middle Ages of the church.

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