By 1052 a great controversy arose between Constantinople and Rome, not only about the filioque, but also about the place of the Roman papacy in the Church, and about divergent liturgical practices in East and West. The immediate cause of the conflict at this time was the Pope's suppression of Greek liturgical practices in South Italy, and the suppression of Latin practices in the East by the patriarch of Constantinople. In 1053 the Pope sent legates to Constantinople in an attempt to restore communion between the churches. Michael Cerularius, the patriarch of Constantinople, refused to give the papal legates a hearing because he thought they were politically motivated.

On July 16, 1054, Cardinal Humbert, the head of the papal delegation, was tired of waiting. He was irritated by the lack of respect shown to the Roman ambassadors, so he placed a document of anathema and excommunication (applying only to the "patriarch Michael Cerularius and those in sympathy with him") on the altar table of the Holy Wisdom (Hagia Sophia) cathedral. At the same time, the cardinal was very careful to praise Constantinople as a "most orthodox city."

The official reasons for Humbert's anathema and excommunication of Cerularius were the removal of the filioque from the Creed; the practice of married clergy; and liturgical errors. Patriarch Michael Cerularius responded to Humbert's action by excommunicating all responsible" for the July 16 incident. He drew up a long list of Latin abuses, mostly of divergent liturgical practices such as the use of unleavened bread for the Eucharist, and the practice of baptism by one immersion.

Although Cardinal Humbert acted only against the person of the patriarch and his sympathizers, and although the patriarch reacted only against Humbert himself, the attempt to restore unity between East and West in 1054 resulted in a permanent schism between the two churches which persists until today. Several gestures of reconciliation, such as the symbolic "lifting of the anathemas of 1054" by Pope Paul VI and Patriarch Athenagoras I in 1966, were made, but to no avail.

The Papacy
The reforming spirit of the Roman papacy reached its height in the eleventh century under Hildebrand who, as Pope Gregory VII (1073-1085), firmly established the papacy as a secular power. In 1089 the East asked Pope Urban II for a confession of faith. He refused to comply since such a compliance would presume that the bishop of Rome could be judged in the Church by another. Thus, although Patriarch Nicholas III of Constantinople (1084-1111) said: "Let the pope confess the orthodox faith and he will be first," this was never again to happen in history.

The Crusades
By the time of the first crusade in 1095 no one in the East doubted that the Pope of Rome was emperor in the West. It was ultimately the crusades which sealed the schism between the churches. The crusaders took over Jerusalem in 1099, expelled the Moslems, and established a Latin hierarchy in place of the local, existing church order.

Kievan Russia
In Kievan Russia in the eleventh century the new Christian faith was flourishing. Saint Anthony (d. 1051) founded the monastery of the caves in Kiev, the Kievo-Pecherskaya Lavra. Saint Theodosius (d.1074), its greatest saint, came to be called the "founder of Russian monasticism." Saint Theodosius followed the example of the humble Christ of the gospels in an evangelical form of spiritual life. This form has come to be known as Russian kenoticism which means a life of self-emptying humility and love for the brethren. (cf. Philippians 2:6) The Kievan Monastery of the Caves was the center of Christian charity and social concern, as well as of spiritual and intellectual labor and enlightenment.

Boris and Gleb
Among the saints of Kiev are numbered the brothers Boris and Gleb who were the sons of Saint Vladimir. They refused to fight their brother Sviatopolk in a power struggle after the death of their father. As they knew that there was no hope of winning in battle, the two young brothers refused to fight in order to save the lives of their faithful followers who were certain to be punished if they did fight. As "sufferers of non-resistance," Saints Boris and Gleb were the first to be canonized by the Russian Church in 1020. They were glorified - not as martyrs or Christian pacifists - but as those who laid down their lives that others might live.

Theological Works
During this period Saint Theophylactus of Bulgaria was writing voluminous commentaries on the holy scriptures in the East. Anselm of Canterbury (d.1109) in the West was producing his most influential theological discourses which contained the so-called "ontological proof" for the existence of God, a defense of the doctrine of the filioque, and the so-called "satisfaction theory" of the atonement in which it was contended that the death of Christ on the cross was the adequate sacrifice necessary to satisfy the justice and wrath of God the Father.

The Western Church
The eleventh century in the West witnessed the Cistercian reforms of the Benedictine order (now known as the "trappists"). This movement's greatest representative, Bernard of Clairvaux was an ascetical, mystical theologian and church activist. He preached crusades and fought with Abelard, the famous author of Sic et Non. The Carthusian movement of eremitic monasticism began as well at this time.

From: Bible and Church History by Fr. Thomas Hopko, Dept. of Religous Education - Orthodox Church in America, Crestwood, New York