The great divorce | Christian History Magazine

On July 20, 1054, Patriarch of Constantinople Michael Caerularius, as head of a Synod held in Constantinople excommunicated Humbert of the Western church (Rome). An excerpt from the article:

"In addition there was a significant difference between the educated. Byzantium was a civilization of great wealth and learning, and many educated laymen took an active interest in theology. The lay theologian has always been an accepted figure in Orthodoxy: some of the most learned Byzantine patriarchs Photius, for example were laymen before their appointment to the patriarchate.

In the West, mired in political confusion and cultural retreat, the only effective education that survived the early Middle Ages (often called the “dark” ages) was given solely to the clergy. Theology became the preserve of priests. Most of the laity were illiterate; most could not comprehend the nuances of theological discussion.

So theology took different paths, East and West. In general the Latin approach was more practical, the Greek more speculative. Latin thought was influenced by Roman law, while Greeks understood theology in the context of worship. Regarding the Crucifixion, Latins thought primarily of Christ the victim on the Cross, Greeks of Christ the victor over death. Latins talked more about redeeming sinners, Greeks, about the deification of humanity.

There were also a few practical differences: the Greeks allowed married clergy; the Latins insisted on priestly celibacy. The two sides had different rules about fasting. The Greeks used leavened bread in the Eucharist, the Latins unleavened bread, or “azymes"...

...the Greeks, singling out the points where Byzantine practice differed from their own: married clergy, rules of fasting, and above all the filioque.

This last dispute involved the words about the Holy Spirit in the Nicene Creed. Originally the phrase read: “I believe in the Holy Spirit, the Lord, the Giver of Life,who proceeds from the Father . “ This original form is still recited unchanged by the East to this day. But the West gradually had inserted an extra phr“and from the Son” (in Latin, filioque), so that in the West, the Creed read “ who proceeds from the Father and the Son.”

The addition originated in Spain in the sixth century as a safeguard against Arianism; it helped emphasize the full divinity of Jesus. The addition spread to France and Germany, where it was welcomed by Charlemagne and adopted at the Council of Frankfurt (794).

Rome did not use the filioque until the start of the eleventh century. In 808 Pope Leo III wrote Charlemagne that, although he himself believed the filioque to be doctrinally sound, he considered it a mistake to tamper with the wording of the Creed."