Apostolic succession is the method whereby the ministry of the Christian Church is considered by some Christian denominations to be derived from the apostles by a continuous succession, which has usually been associated with a claim that the succession is through a series of bishops. Those of the Catholic, Eastern Orthodox, Scandinavian Lutheran, Anglican, Oriental Orthodox, Church of the East, Hussite, Moravian, and Old Catholic traditions maintain that "a bishop cannot have regular or valid orders unless he has been consecrated in this apostolic succession". These traditions do not always consider the episcopal consecrations of all of the other traditions as valid.
The World Council of Churches (WCC) is a worldwide Christian inter-church organization founded in 1948 to work for the cause of ecumenism. Its full members today include the Assyrian Church of the East, the Oriental Orthodox Churches, most jurisdictions of the Eastern Orthodox Church, the Union of Utrecht, the Lutheran World Federation, the Anglican Communion, the Mennonite churches, the World Methodist Council, the Baptist World Alliance, the World Communion of Reformed Churches, the Pentecostal churches, the Moravian Church and the Malankara Mar Thoma Syrian Church. Notably, the Catholic Church is not a full member, although it sends delegates who have observer status to meetings.
Ecumenism – also called interdenominationalism, or ecumenicalism – is the concept and principle that Christians who belong to different Christian denominations should work together to develop closer relationships among their churches and promote Christian unity. The adjective ecumenical is thus applied to any non-denominational or inter-denominational initiative which encourages greater cooperation and union among Christian denominations and churches. Ecumenical dialogue is a central feature of contemporary ecumenism.
The Eastern Catholic Churches or Oriental Catholic Churches, also called the Eastern-Rite Catholic Churches, Eastern Rite Catholicism, or simply the Eastern Churches, are 23 Eastern Christian autonomous particular churches of the Catholic Church, in full communion with the pope in Rome. Although they are distinct theologically, liturgically, and historically from the Latin Church, they are all in full communion with it and with each other. Eastern Catholics are a minority within the Catholic Church; of the 1.3 billion Catholics in communion with the pope, approximately 18 million are members of the eastern churches. The largest numbers of Eastern Catholics may be found in Eastern Europe, Eastern Africa, the Middle East, and India. As of 2022, the Syro-Malabar Church is the largest Eastern Catholic Church, followed by the Ukrainian Greek Catholic Church.
Closed communion is the practice of restricting the serving of the elements of Holy Communion to those who are members in good standing of a particular church, denomination, sect, or congregation. Though the meaning of the term varies slightly in different Christian theological traditions, it generally means that a church or denomination limits participation either to members of their own church, members of their own denomination, or members of some specific class. This restriction is based on various parameters, one of which is baptism. See also intercommunion.
Open communion is the practice of some Protestant Churches of allowing members and non-members to receive the Eucharist. Many but not all churches that practice open communion require that the person receiving communion be a baptized Christian, and other requirements may apply as well. In Methodism, open communion is referred to as the open table, meaning that all may approach the Communion table.
The East–West Schism, also known as the Great Schism or the Schism of 1054, is the break of communion between the Catholic Church and the Eastern Orthodox Church since 1054. A series of ecclesiastical differences and theological disputes between the Greek East and Latin West preceded the formal split that occurred in 1054. Prominent among these were the procession of the Holy Spirit (Filioque), whether leavened or unleavened bread should be used in the Eucharist, iconoclasm, the coronation of Charlemagne as Emperor of the Romans in 800, the Pope's claim to universal jurisdiction, and the place of the See of Constantinople in relation to the pentarchy.
In Christian theology, ecclesiology is the study of the Church, the origins of Christianity, its relationship to Jesus, its role in salvation, its polity, its discipline, its eschatology, and its leadership.
Ut unum sint is an encyclical on ecumenism by Pope John Paul II of 25 May 1995. It was one of 14 encyclicals he issued, and Cardinal Georges Cottier, Theologian Emeritus of the Pontifical Household, was influential in its drafting.
The Catholic Church has engaged in the modern ecumenical movement especially since the Second Vatican Council (1962–1965) and the issuing of the decree Unitatis redintegratio and the declaration Dignitatis humanae. It was at the Council that the Pontifical Council for Promoting Christian Unity was created. Those outside of the Catholic Church were categorised as heretics or schismatics, but in many contexts today, to avoid offence, the euphemism "separated brethren" is used.
Branch theory is an ecclesiological proposition that the One, Holy, Catholic, and Apostolic Church includes various different Christian denominations whether in formal communion or not. The theory is often incorporated in the Protestant notion of an invisible Christian Church structure binding them together.
Elias Zoghby was an Egyptian-born Lebanese Catholic prelate who served as Archbishop of Baalbek in the Melkite Greek Catholic Church from 1968 to 1988. He was known as a leading advocate of Catholic–Orthodox ecumenism. He is best known for his ecumenical interventions during the Second Vatican Council and for his 1995 Profession of Faith, known as the Zoghby Initiative, which attempted to re-establish communion between the Melkite Greek Catholic Church and the Eastern Orthodox Church.
The historic or historical episcopate comprises all episcopates, that is, it is the collective body of all the bishops of a group who are in valid apostolic succession. This succession is transmitted from each bishop to their successors by the rite of Holy Orders. It is sometimes subject of episcopal genealogy.
Paul Irénée Couturier was a French Catholic priest and a promoter of the concept of Christian unity. He was instrumental in the establishment of the Week of Prayer for Christian Unity.
Anglican interest in ecumenical dialogue can be traced back to the time of the Reformation and dialogues with both Orthodox and Lutheran churches in the sixteenth century. In the nineteenth century, with the rise of the Oxford Movement, there arose greater concern for reunion of the churches of "Catholic confession". This desire to work towards full communion with other denominations led to the development of the Chicago-Lambeth Quadrilateral, approved by the Third Lambeth Conference of 1888. The four points were stipulated as the basis for church unity, "a basis on which approach may be by God's blessing made towards Home Reunion":
The Oriental Orthodox Churches are Eastern Christian churches adhering to Miaphysite Christology, with approximately 50 million members worldwide. The Oriental Orthodox Churches adhere to the Nicene Christian tradition. Oriental Orthodoxy is one of the oldest branches in Christianity.
Pope Benedict XVI, who led the Roman Catholic Church as Pope from 2005 to 2013, continued manoeuvring the Church through the dynamics of modernity, which the Church had begun engaging in with the Second Vatican Council. Because the question of religious pluralism is a key issue raised by modernity, ecumenism, the establishment of harmony and dialogue between the different Christian denominations, is a significant concern of a post Second Vatican Council Church. Pope Benedict XVI's approach has been characterised as leaning toward the conservative while still being expansive and engaged, involving the full breadth of Christendom, including the Orthodox Churches and Protestant churches, as well as freshly engaging with other Christian bodies considered by Roman Catholics to be more heterodox, such as the Church of Jesus Christ of Latter-day Saints.
The Dicastery for Promoting Christian Unity, previously named the Pontifical Council for Promoting Christian Unity (PCPCU), is a dicastery within the Holy See whose origins are associated with the Second Vatican Council which met intermittently from 1962 to 1965.
Gerhard Ludwig Müller is a German Catholic prelate who served as the Cardinal-Prefect of the Congregation for the Doctrine of the Faith from his appointment by Pope Benedict XVI in 2012 until 2017. Pope Francis elevated him to the rank of cardinal in 2014.
David John Bird is dean emeritus of the historic Trinity Episcopal Cathedral, the oldest church structure in continuous use in San Jose. He is a parish priest who reads and writes poetry and is particularly fond of Alfred Lord Tennyson. As a theologian, he emphasizes a liberal, compassionate, and inclusive approach and is devoted to ecumenism. Bird promotes Christian unity and is published in this field; since 2002, he has served on the national Committee of The Episcopal Church-United Methodist Church Dialogue.
