Although many events from medieval Church history seem to have been guided by the power of the Pope, head pastor in Rome and (according to the various popes) Vicar of Jesus Christ on Earth, Christianity was never united under a single worldly leader. Jesus Christ and the Bible unite Christians in heaven and on earth. Other attempts to impose unity and conformity upon Christians result only in division, separation, and sometimes violent opposition.
In early Church times, leaders of the Church in five cities were generally respected as foremost among Christians on Earth. Those cities were Rome, Constantinople, Antioch, Jerusalem, and Alexandria. Councils that discussed and defined the teachings of the Church did not submit to any of these five bishops; one council even condemned Pope Honorius as a heretic!
The sudden appearance of Islam overwhelmed the congregations in Alexandria, Jerusalem, and Antioch. While they still existed, they were much smaller and exerted little influence on the rest of Christianity. Given two powerful centers of the faith, it perhaps was inevitable that a showdown would arise involving the Pope in Rome and the Patriarch in Constantinople.
The groups of Christians led by these two figures disagreed about several matters. Probably the most important theological matter was the question of the Holy Spirit, whether he proceeds from the Father and the Son (as is taught in the western Church) or from the Father alone (as is taught in the eastern Church). A more practical matter on which the groups differed was the question of religious artwork. Byzantine emperors grew increasingly hostile toward artwork in the Church, pointing to the Ten Commandments, which include a prohibition of “graven images.” Defenders of such artwork were able to cite examples of artwork in Scripture—even in the book of Exodus, the same book which contains that prohibition of graven images, but which gives instructions for building the Tabernacle and the Ark of the Covenant. They also indicated that artwork is helpful for teaching and for devotional life, insisting that the Biblical prohibition only forbids worshiping images. A Byzantine Emperor named Leo sent soldiers into churches to destroy images, prompting fierce opposition and large demonstrations from Christians defending the place of art in the Church. The compromise reached in the Byzantine Empire was stricter than Roman leaders liked. Ironically, eastern churches are now known for their icons representing Jesus Christ and certain saints and angels.
The two groups of Christians differed on other subjects as well, such as determining the date of Easter each year, the use of leavened or unleavened bread in Holy Communion (the Lord’s Supper), and other details about Christian life and worship. From a historical point of view, though, the biggest difference in opinion regarded the question of whether the Roman Pope is the head of all true Christians on Earth. In the year 1054, the Pope sent a messenger to Constantinople to lay a message on the altar of Hagia Sophia. This document excommunicated the Patriarch of Constantinople and anyone who agreed with the Patriarch in saying that the Pope is not the head of the Church on Earth. Somewhere between the two cities, the Pope’s messenger passed a messenger sent by the Patriarch excommunicating the Pope and anyone else who says that the Pope is the head of the Church on Earth. From this year until the present, every Christian on Earth has been excommunicated by one of those two documents (and some groups of Christians would be considered outside the Church according to both documents).
Christians who agreed with the Patriarch in Constantinople called themselves “orthodox.” This Greek word means “thinking correctly.” No doubt every Christian calls himself or herself orthodox; each of us believes that he or she has the correct faith. The Christians who agreed with the Pope called themselves “catholic.” This Latin word reflects the unity of the Church and also signifies that it exists everywhere. Again, every Christian would consider himself a member of the true catholic Church. While human organizations among Christians on Earth continue to use these labels, every believer in Jesus Christ in heaven and on earth is a member of the one true Church, which (by definition) is both orthodox and catholic.
Meanwhile, the Pope’s worldly authority over the city of Rome and other parts of Italy involved the Pope in battles with assorted other heads of state in Europe. Italy increasingly became a battleground for armies from the Holy Roman Empire, France, Spain, and other European powers. Finally, to escape the turmoil, Pope Clement V moved himself and his Church government to Avignon. That city today is in France, although in 1305 (when Clement became Pope) it was part of the country ruled from Naples. For seventy years, the Pope and cardinals governed the Church from Avignon. All these popes and most of the cardinals came from France, spoke French, and were politically allied with the government of France.
After Pope Gregory XI died in 1378, a group of Italian cardinals slipped back into Rome and elected Urban VI as Pope. The French cardinals, still in Avignon, proceeded to elect Clement VII. Now there were two popes, and Christians in Europe had to decide which of them was their head. Bishops and archbishops took sides; secular government took sides. Both popes died and were replaced with new popes by their respective groups of cardinals. Finally, in 1409, a church meeting in Pisa fired both popes and elected a new pope, named Alexander V. Unfortunately, neither of the other popes believed that he was fired, and now Christians had to choose from among three earthly heads.
Five years later, another church meeting was held in the city of Constance. Before electing a new pope, the leaders of the council persuaded all three current popes to resign. Two did so quickly—one even before the council began—hoping that their willingness to cooperate would buy them votes. The third held out for a while but eventually also resigned. All three were sent into retirement, and the Council of Constance elected Martin V to serve the Church as pope.
For a while, some Christians hoped that the power of popes would be reduced by these years of chaos and struggle. They hoped that Church Councils could provide leadership for Christians and could reunite Christians living on Earth. Instead, popes from this time onward insisted that only the Pope can convene church councils and that the Pope can instruct those councils how to vote and can overrule their decisions. Meanwhile, other Christian movements were brewing, movements that would produce further chaos and would provide even greater challenges to the popes in Rome. J.