Questions Answered – September 2025

The “Great Schism”: What Happened and Why?

Question: Dear Father Cush, why did the Catholic Church and the Orthodox Church split? What does the Catholic Church teach about receiving the Sacraments in the Orthodox Churches?  

Answer: The division between the Catholic Church and the Orthodox Church is one of the most significant events in Christian history, and its roots lie in both theological and political differences that developed over centuries. This split, known as the Great Schism of 1054, marked the separation of the Eastern (Orthodox) and Western (Catholic) branches of Christianity.

While the Catholic and Orthodox Churches share many common teachings, certain theological disagreements contributed to the schism, especially the phrase “Filioque” (Latin for “and the Son”) which was added to the Nicene Creed by the Western Church to express the belief that the Holy Spirit proceeds from both the Father and the Son. The Eastern Church rejected this addition, arguing that the Holy Spirit proceeds only from the Father, as originally stated in the Creed.

The supremacy of the Pope, who is seen by Catholics as the supreme authority on earth, was not accepted by the Eastern Churches. The Orthodox Church views the Patriarch of Constantinople (and other bishops) as having a primacy of honor but not of jurisdiction over all Christians. This difference in views of papal authority was a key theological issue that contributed to the schism.

While both Churches believe in the Real Presence of Christ in the Eucharist, the Catholic Church teaches the doctrine of transubstantiation, which holds that the bread and wine become the actual Body and Blood of Christ. While the Orthodox also believe in the Real Presence, they do not define this doctrine in the same precise terms, leading to some differences in understanding.

By the time of the schism, the Western Church (centered in Rome) spoke Latin, and the Eastern Church (centered in Constantinople) spoke Greek. These linguistic and cultural barriers made communication and understanding more difficult.

In addition to theological differences, there were growing political tensions between the Eastern (Byzantine) and Western (Roman) Empires. The fall of the Western Roman Empire and the rise of the Holy Roman Empire also intensified the divide. The Western Pope began to assert authority over territories and rulers that the Eastern Church did not recognize.

The final rupture in 1054 occurred when Pope Leo IX and Patriarch Michael I of Constantinople excommunicated each other. The excommunications were partly over theological and political disagreements, but they symbolized the growing estrangement between the two churches. Though there were attempts at reconciliation over the centuries, the schism remained.

The Catholic Church teaches that, although there is a division between the Catholic and Orthodox Churches, there remains significant shared sacramental life and apostolic succession. The Catholic Church recognizes the validity of the sacraments celebrated in the Orthodox Church, including the Eucharist. The Orthodox Church maintains valid apostolic succession (the uninterrupted transmission of spiritual authority from the apostles through successive bishops) and the correct form and matter for the sacraments. The Catechism of the Catholic Church (CCC), 1400 states, “The Eucharist is the source and summit of the Christian life. . . . The Church recognizes in the Eastern Orthodox Churches the valid celebration of the Eucharist, despite the lack of full communion between the Orthodox and Catholic Churches.”

Baptism is also recognized as valid in the Orthodox Church, provided it is performed using the proper matter (water) and the Trinitarian formula (“In the name of the Father, and of the Son, and of the Holy Spirit”).

Catholics are not typically encouraged to receive the sacraments in Orthodox Churches, except under certain conditions (e.g., in danger of death or when no Catholic priests are available). This is because the Catholic Church desires full communion with the Orthodox Church, which has been broken since the Great Schism. The conditions for receiving sacraments in the Orthodox Church are as follows: first, if a Catholic is in danger of death and cannot receive the sacrament from a Catholic priest, they may receive sacraments from the Orthodox Church; second, in situations where no Catholic priest is available, a Catholic may receive sacraments in an Orthodox Church, as long as the person maintains their Catholic faith. The CCC, 1401, states: “When necessity requires it or in the absence of a Catholic priest, the faithful may receive the sacraments of the Eucharist, Penance, and Anointing of the Sick from a validly ordained Orthodox priest.”

Although the sacraments are valid, full communion between the Catholic and Orthodox Churches is still lacking. The division over papal authority remains a barrier. The Catholic Church desires reconciliation and full unity with the Orthodox Church, as expressed in documents like the Second Vatican Council’s Unitatis Redintegratio (Decree on Ecumenism).

While Catholics can participate in the sacraments of the Orthodox Church under certain conditions, they are encouraged to maintain unity with the Pope and the Catholic Church, and should seek reconciliation with the Church whenever possible. Despite the schism, both the Catholic and Orthodox Churches have made efforts to reconcile and pursue ecumenical dialogue. The Second Vatican Council and subsequent papal statements (e.g., from Popes John Paul II, Benedict XVI, and Francis) have sought to promote unity between the two Churches, acknowledging shared beliefs and practices while recognizing the ongoing theological differences that need resolution.

Why Are Protestant Communities Not “Churches”?

Question: Father, as a follow-up question, why does the Catholic Church refer to the Protestant churches as “ecclesial communions” rather than “Churches”?

Answer: The Catholic Church refers to Protestant communities as ”ecclesial communions” rather than ”Churches” due to both theological and ecclesiological reasons. The distinction is rooted in the Catholic understanding of the Church and its relationship to the full apostolic succession and the fullness of the means of salvation.

In Catholic teaching, the Church is not merely a community of believers, but a divine institution founded by Christ to continue His mission on earth. It is the Body of Christ and the People of God, entrusted with the fullness of the means of salvation, including the sacraments, the apostolic ministry, and the Magisterium (teaching authority). The Catholic Church believes that it alone, through its unbroken apostolic succession (the line of bishops traced back to the apostles) and the papacy (the office of the Pope as the successor of Saint Peter), possesses the fullness of the Church’s essential elements. The Catechism of the Catholic Church (CCC), 811, states: “The Church, which is one, holy, catholic, and apostolic, has been sent by Christ on a mission to the whole of the human race. . . . In Christ, the Church is the sacrament of salvation, the sign and instrument of the communion of God and men.”

While the Catholic Church recognizes that Protestant communities are Christian and have elements of truth and sanctification, it also believes that these communities lack some of the essential characteristics of the full Church as defined in Catholic theology. Therefore, the term “ecclesial communion” is used to indicate that these communities are part of the broader Christian family but do not have the fullness of the Church’s structure and means of grace. The Catholic Church teaches that valid apostolic succession (the unbroken line of bishops going back to the apostles) is essential for the Church’s full sacramental life, particularly in the Eucharist and the sacraments of Holy Orders. Most Protestant communities do not maintain this line of succession and, therefore, the Catholic Church does not consider them to have the fullness of the priesthood.

In addition, while many Protestant communities believe in the Real Presence of Christ in the Eucharist (though often in a symbolic or spiritual sense), the Catholic Church teaches that the Eucharist is the true Body and Blood of Christ, and only those in full communion with the Church can receive it properly. The Catholic Church believes that Protestant communities lack the fullness of the Eucharistic sacrament.

The Catholic Church holds that the Pope, as the successor of Saint Peter, has a unique role of authority and unity in the Church, which is essential for maintaining the unity of the faith and the teaching authority (the Magisterium). Since Protestant communities generally do not accept the papacy, they lack this full communion with the See of Peter.

At the same time, the Catholic Church recognizes that Protestant communities have elements of truth and that the Holy Spirit is at work in them. The Church acknowledges that these communities can offer valuable spiritual insights and that they share in Christian baptism, which is a means of salvation. However, because of the lack of the full sacramental and doctrinal unity (as described above), the Church does not refer to them as “Churches” in the fullest sense. Unitatis Redintegratio, the Second Vatican Council’s Decree on Ecumenism (1964), §3 states: “For men who believe in Christ and have been properly baptized are put in some, though imperfect, communion with the Church. There is, therefore, a certain communion, though imperfect, between the Catholic Church and the Christian communities.”

The term “ecclesial communion” emphasizes the partial communion Protestant communities have with the Catholic Church, while acknowledging that there is still a lack of fullness in terms of doctrine, sacramental life, and authority. The Catholic Church maintains that, for a Christian community to be considered a full “Church” in the Catholic sense, it must have the complete structure established by Christ, which includes the fullness of apostolic succession, the sacraments, and the authority of the Pope.