The Great Schism of 1054
Schism is defined as a split or division between strongly opposed parties, usually cause by a difference in opinion or beliefs. The Great Schism of 1054 was the breakup of the Christian Church into two sections – the Western and the Eastern sections.

In history, there have been many schisms within the Catholic Church. The most notable were the Arianism, the Nestorian and Monophysite which still lasts today. But the most notable quarrel was the Eastern Schism of 1054 which resulted in the separation of the majority of Eastern Christians from the alliance with the Catholic Church. This schism produced the Orthodox Church.
What was the disagreement that caused this quarrel where nearly half of Christendom fell away? It wasn’t about faith or rival theology; in my opinion it was about lack of communication caused by anger and bad feelings between groups within the Catholic Church of a gradual process than can be traced back centuries before there was any suspicion of the final separation.
Even though Christianity and Orthodox churches both have valid holy orders and apostolic succession, both celebrate the same sacraments, both believe almost the same theology, and both proclaim the same faith in Jesus Christ. So, why the division? To understand this, let’s go back a few centuries and see the division fester.
After the Roman Empire collapsed in 476 A.D., the eastern half of the empire continued under the Byzantine Empire with headquarters in Constantinople. The church was soon organized into patriarchates (heads of states) with the patriarch of Constantinople having jurisdiction over the patriarchs of Alexandria, Antioch, and Jerusalem. The patriarch of Constantinople then served under the military rule of an emperor who had tremendous influence in church affairs (the same situation during the time of Jesus by the Roman occupying forces). So much influence was asserted that emperors claimed to be equal in authority to the twelve apostles, and as a result claim to have power to appoint the bishop position of Constantinople. This did not sit well with Rome.
After the death of Muhammad, his followers launched a jihad to conquer the entire world. Muslims quickly gained control of the patriarchates of Jerusalem, Antioch and Alexandria, and leaving Constantinople as the only unoccupied eastern patriarchate. Continued attacks from the Barbarians left the papacy as the dominant entity in Rome. This too was a cause of friction, as several patriarchs felt the papacy had gained excessive prominence.
Eastern patriarchs did not always recognize the pope’s authority in all matters, and after the 11th century, few eastern Christians did not recognize that authority. Although both sides shared a common doctrine and heritage, it was no longer united with the Roman Catholic Church. At the heart of the brake was the Roman pope’s claim to universal jurisdiction and authority. The Orthodox Church in the East agreed to honor the pope’s suggestion of authority but believed that a council of bishops should decide ecclesiastical matters, and therefore, challenged the sole dominion of the pope.
There were other divisions such as the nature of the incarnate Christ, specifically whether Jesus Christ had one divine-human nature or two distinct natures (divine and human). Other dissenting opinions were centered on clerical celibacy, fasting, anointing with oil, and the procession of the Holy Spirit. They also disagreed on whether it was acceptable to use unleavened bread for communion ceremonies. Western churches supported the practice, while Greeks used leavened bread in the Eucharist.
During the eighth and ninth centuries, controversy also arose about the use of icons in worship. Then Byzantine Emperor Leo III declared that the worship of religious images was heretical. But the Western Church stood firm in support of the use of religious images.
The most critical controversy was the dispute around the Trinity doctrine, and whether the Holy Spirit proceeded from God the Father alone or from both the Father and the Son. Originally, the Nicene Creed simply said that the Holy Spirit “proceeds from the Father.” Western Church added a clause (named the Filioque Cause) to the creed to suggest that the Holy Spirit proceeds from both the Father “and the Son.” The Easter Church insisted on keeping the original wording and that the West had no right to alter the foundational creed of Christianity. Both leaders refused to budge or compromises leading to the Eastern bishops accusing the pope and bishops in the West of heresy. In the end, the two churches forbade the use of the other church’s rites and excommunicated one another from the true Christian church.
On July 16, 1054, Patriarch of Constantinople Michael Cerularius was excommunicated from the Catholic church by Pope Leo IX. This resulted in the permanent separation between the Roman Catholic Church and Eastern Orthodox, Greek Orthodox, and Russian Orthodox Churches. Recent relations between East and West have somewhat improved, but to date, the churches still are divided.