Branch theory
Branch theory is an ecclesiological proposition that the One, Holy, Catholic, and Apostolic Church includes various 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.
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Anglican proponents of Anglo-Catholic churchmanship who support the theory include only the Roman Catholic, Eastern Orthodox, Oriental Orthodox, Scandinavian Lutheran, Old Catholic, Moravian, Persian and Anglican churches as branches.[1] On the other hand, the majority of Anglicans, including those of low church, broad church and high churchmanship, have "followed the major continental Reformers in their doctrine of the true church, identifiable by the authentic ministry of word and sacrament, in their rejection of the jurisdiction of the pope, and in their alliance with the civil authority ('the magistrate')".[2] The Church of England historically considered itself "Protestant and Reformed" and recognized as true churches the Continental Reformed Churches, participating in the Synod of Dort in 1618-1619.[2] As such, Anglicans have entered into full communion with bodies such as the Evangelical Church in Germany and in some countries, have merged with Methodist, Presbyterian and Lutheran denominations to form united Protestant Churches, such as the Church of North India, Church of Pakistan, Church of South India, and the Church of Bangladesh for example.[2] For Anglicans of Evangelical churchmanship, the notion of apostolic continuity is seen as "fidelity to the teaching of the apostles as set out in scripture, rather than in historical or institutional terms" and thus they place focus on "the gospel, and the means by which this is proclaimed, articulated, and reinforced--namely, the ministers of word and sacrament."[3]
Other Protestant Christians, including Evangelical Anglicans, generally reject the Anglo-Catholic version of the branch theory and hold a theory in which the Christian Church "has no visible unity" but contains numerous denominations that are "invisibly connected."[4] Fortescue states that "this theory is common among all Protestant bodies, although each one generally holds that it is the purest branch."[4]
In expounding upon branch theory, theologian Paul Evdokimov states that some view each distinct Christian tradition as contributing something special to the whole of Christendom:
... the famous "branch theory", according to which each ecclesiastical tradition possesses only part of the truth, so that the true Church will come into being only when they all join together; such a belief encourages the "churches" to continue as they are, confirming in their fragmented state, and the final result is Christianity without the Church. Each church, in its more pronounced form, displays, according to its own native spirit, a particular version of the unique revelation. So, for example, Roman Christianity is characterized by filial love and obedience expressed towards the fatherly authority hypostatized in the first Person of the Trinity: the Church is there to teach and to obey. For the Reformed Churches the vital thing is sacramental reverence for the Word; it is the Church's duty to listen and reform itself. The Orthodox treasure the liberty of the children of God that flowers in liturgical communion, while the Church hymns the love of God for the human race.[5]
Views
Anglican
Charles Daubeny (1745-1827) formulated a branch theory in which the One, Holy, Catholic, and Apostolic Church included the Anglican, Scandinavian Lutheran, Roman Catholic and Eastern Orthodox Churches;[6] to this the Oriental Orthodox Churches, Moravian Church, Church of the East, and Old Catholic Churches were also added.[1] The theory was popularized during the Oxford Movement, particularly through the work of the Tractarians. Although the Anglican Roman Catholic International Commission, an organization sponsored by the Anglican Consultative Council and the Pontifical Council for Promoting Christian Unity, seeks to make ecumenical progress between the Roman Catholic Church and the Anglican Communion, it has made no statement on the topic. The theory "has received mixed reception even within the Anglican Communion."[7] The majority of Anglicans, including those of low church, broad church and high churchmanship, have "followed the major continental Reformers in their doctrine of the true church, identifiable by the authentic ministry of word and sacrament, in their rejection of the jurisdiction of the pope, and in their alliance with the civil authority ('the magistrate')".[2] The Church of England historically considered itself "Protestant and Reformed" and recognized as true churches the Continental Reformed Churches, participating in the Synod of Dort in 1618-1619;[2] in 1567, Edmund Grindal, who became the Church of England's Archbishop of Canterbury, declared that "all reformed churches do differ in rites and ceremonies, but we agree with all reformed churches in substance of doctrine."[8] As such, Anglicans have entered into full communion with bodies such as the Evangelical Church in Germany and in some countries, have merged with Methodist, Presbyterian and Lutheran denominations to form united Protestant Churches, such as the Church of North India, Church of Pakistan, Church of South India, and the Church of Bangladesh for example.[2] For Anglicans of Evangelical churchmanship, the notion of apostolic continuity is seen as "fidelity to the teaching of the apostles as set out in scripture, rather than in historical or institutional terms" and thus they place focus on "the gospel, and the means by which this is proclaimed, articulated, and reinforced--namely, the ministers of word and sacrament."[3]
Catholic
The Catholic Church does not accept that those churches separated by schism or heresy are fully part of the one church, maintaining that "there exists a single Church of Christ, which subsists in the Catholic Church, governed by the Successor of Peter and by the Bishops in communion with him".[9] The Catholic Church rejects the validity of Anglican Orders, defined formally in 1896 by Pope Leo XIII in the Papal Bull Apostolicae curae, which declares Anglican Orders "absolutely null and utterly void".
Soon after the formulation of the branch theory, in 1864, the Holy Office rejected the branch theory or idea that "the three Christian communions, Catholic, Greek schismatic, and Anglican, however separated and divided from one another, nevertheless with equal right claim for themselves the name "Catholic" and "together now constitute the Catholic Church".[10] In 1870, English bishops attending the First Vatican Council raised objections to the expression Sancta Romana Catholica Ecclesia ("Holy Roman Catholic Church") which appeared in the schema (the draft) of the First Ecumenical Council of the Vatican's Dogmatic Constitution on the Catholic Faith, Dei Filius. These bishops proposed that the word "Roman" be omitted or at least that commas be inserted between the adjectives, out of concern that use of the term "Roman Catholic" would lend support to proponents of the branch theory. While the council overwhelmingly rejected this proposal, the text was finally modified to read "Sancta Catholica Apostolica Romana Ecclesia" translated into English either as "the holy Catholic Apostolic Roman Church" or, by separating each adjective, as "the holy, catholic, apostolic, and Roman Church".
Both lungs concept
Pope Benedict XVI and Pope John Paul II used the "two lungs" concept to relate Catholicism with Eastern Orthodoxy.[11]
Eastern Orthodox
Non-acceptance of the branch theory by the Eastern Orthodox Church,[12] was in 1853 called unfortunate by the theory's founder, William Palmer, who wished the Eastern Church to claim to be no more than a part of the whole, not the whole of the true Church.[13] Bishop Kallistos Ware says that "Orthodox writers sometimes speak as if they accepted the 'Branch Theory', once popular among High Church Anglicans", but explains that this opinion "cannot be reconciled with traditional Orthodox theology".[14] Western Orthodox cleric Julian Joseph Overbeck writes:
But what do we see in the Anglican Church? Heresies are not only tolerated and publicly preached from the pulpits, and the schismatical and heretical Church of Rome is by a great many fondled and looked up to, but a theory has sprung up, the so called Branch-Church theory, maintaining that the Catholic Church consists of three branches: the Roman, Greek, and Anglican Churches. Only fancy! the Roman and Greek Churches contradicting and anathematising each other, and the Anglican Church (in its Articles) contradicting both, and besides full of heretical teaching-these are the component parts of the One Catholic Church, the abode of the Spirit of Truth!!! And on this theory rests the "Corporate Reunion of Christendom," which entirely ignores all Apostolic teaching concerning schism and heresy![15]
In its official declarations, the Eastern Orthodox Church states that the one true church founded by Jesus Christ is a real identifiable entity and that it is singularly the Orthodox Catholic Church. It has identified itself as the "One, Holy, Catholic, and Apostolic Church" in, for instance, synods held in 1836 and 1838 and in its correspondence with Pope Pius IX and Pope Leo XIII.[16] Adrian Fortescue wrote of the Eastern Orthodox: "The idea of a church made up of mutually excommunicate bodies that teach different articles of faith and yet altogether form one Church is as inconceivable to them as it is to us (Catholics)".[17] The Eastern Orthodox Church regards neither Catholics nor Protestants as branches of the "One True Church".[18]
The Eastern Orthodox Church is a part of several ecumenical efforts on international, national, and regional levels, such as the World Council of Churches.[19] With respect to branch theory, some conservative Eastern Orthodox, however, take a decidedly anti-ecumenical stand. For example, in 1983 Metropolitan Philaret (Voznesensky) and the Holy Synod of Bishops of the Russian Orthodox Church Outside Russia stated:
Those who attack the Church of Christ by teaching that Christ's Church is divided into so-called "branches" which differ in doctrine and way of life, or that the Church does not exist visibly, but will be formed in the future when all "branches" or sects or denominations, and even religions will be united into one body; and who do not distinguish the priesthood and mysteries of the Church from those of the heretics, but say that the baptism and eucharist of heretics is effectual for salvation; therefore, to those who knowingly have communion with these aforementioned heretics or who advocate, disseminate, or defend their new heresy of Ecumenism under the pretext of brotherly love or the supposed unification of separated Christians, Anathema![20]
In addition, the Jubilee Council of 2000 of the Church of Russia also condemned "Divided Church" Ecclesiology or the so-called Branch Theory.[21]
Oriental Orthodoxy
It is considered by many that the Chalcedonian Schism resulted from a difference in semantics rather than actual doctrine, stating that both non-Chalcedonian and Chalcedonian Christianity share a similar Christology despite choosing to express it in different (Cyrillian vs. Chalcedonian) terms,[22] and theological dialogue has resulted in formal statements of agreement on that issue, which have been officially accepted by groups on both sides.[23][24] The Orthodoxy Cognate PAGE Society (Society for Orthodox Christian Unity and Faith), which is headquartered in India declares the Society's firm belief that, although "the two groups are not in communion with each other",[25] "both the Byzantine (Eastern) Orthodox Churches and the Oriental Orthodox Churches are the true heirs to the One, Holy, Catholic and Apostolic Church of Christ, which was the Church of the apostles and the holy fathers. We also believe these Churches teach the true faith and morals of the Church established by Christ for which the ancient martyrs gave their lives."[26]
Methodist
The Methodist Church holds to a variation of the branch theory ecclesiology, "advocating that Christianity is represented by three branches: Orthodox, Roman Catholic, and Protestant."[27]
Analogous theories
Branches of the Evangelical Church theory
In Church Dogmatics, Karl Barth, defined the "Evangelical Church" as having three branches: Lutheran, Reformed, and Anglican.[28] The "Evangelical Church" was to be distinguished from what he termed the "three heresies of Neoprotestantism, Roman Catholicism and Eastern Orthodoxy".[28]
Sister churches theory
What has been called another version of the branch theory was propounded in the wake of the Second Vatican Council by some Roman Catholic theologians, such as Robert F. Taft[29][30] Michael A. Fahey,[31][32] and others.[33] In this theory, the Eastern Orthodox Church and the Roman Catholic Church are two "sister churches". This theory was rejected outright by the Catholic Church, which applies the term "sister Churches" only to the relations between particular Churches, such as the sees of Constantinople and Rome.[34]Most Eastern Orthodox theologians also reject it.[35]
A writer in the United States publication Orthodox Life says that ecumenism promotes the idea of a Church comprising all baptized Christians and within which the different confessions are "sister churches".[35]
Two lungs theory
The metaphor of Christianity compared to one body breathing with two lungs was coined by the Russian poet and philosopher Vyacheslav Ivanov, inspired by the worldview of the 19th century Russian philosopher Vladimir Solovyov.[36] Solovyov "felt that eastern Christians could learn from the Western church's relatively active presence in the world."[37]
Ivanov accepted "the idea of 'Unia'", according to Robert Bird, the "combination of traditional rite and papal authority explains why Ivanov felt he was now breathing with both lungs." Pope John Paul II, according to Bird, "adopted Ivanov's imagery of the two 'lungs' of the universal Church" but John Paul II's "image of the full Church seems to presume their equal coexistence, supposedly without the submission of the East to papal authority."[38]
John Paul II used the two lungs of a single body metaphor in the context of "the different forms of the Church's great tradition" in Redemptoris Mater (1987).[39] John Paul II used the metaphor to "the Church", which for him was not some amalgam of the Catholic and Eastern Orthodox Church, but the Catholic Church itself, thus indicating that the Catholic Church must avail itself of the traditions of both Eastern Christianity and Western Christianity.[40][41] The Catholic Church uses this metaphor to compare the Latin Church's tradition to the Eastern Orthodox Churches' traditions and also Eastern Catholic Churches' traditions,[42][43] as emphasized in the Second Vatican Council's Orientalium ecclesiarum, the decree on Eastern Catholic Churches.[44] John Paul II elaborated the metaphor, in Sacri Canones (1990), "the Church itself, gathered in the one Spirit, breathes as though with two lungs – of the East and of the West – and that it burns with the love of Christ in one heart having two ventricles."[43]
An anonymous author wrote, in Orthodox Life magazine, that the metaphor comparing the Eastern Orthodox Church and the Roman Catholic Church to two lungs of one body was "shaped and influenced by" the branch theory and developed by "Orthodox ecumenists and Papists".[45] Eastern Orthodox reject as incompatible with the Orthodox faith any such use of the "two lungs" expression to imply that the Eastern Orthodox and Roman Catholic churches are two parts of a single church and "that Orthodoxy is only for Easterners, and that Catholicism is only for Westerners", according to Archpriest Andrew Phillips.[46] Patriarch Bartholomew I of Constantinople "rejects the opinion" that "there would be an 'incompatibility between Orthodox tradition and the European cultural way', which would be antinomic" and points out that idea "is against the principle of equality and respect of peoples and cultural traditions on our continent."[47][48]
Ion Bria wrote in 1991 that the metaphor "may be attractive as an aid for understanding the formation of two distinctive traditions in Christianity after A.D. 1054."[48] In 2005, Bishop Hilarion Alfeyev, chairman of the Representation of the Russian Orthodox Church to the European Institutions, told the 6th Gniezno Convention that the metaphor is "particularly relevant" when he "proposed to form a European Catholic-Orthodox Alliance" and said "nothing should prevent us from uniting our efforts in order to defend Christian tradition, without waiting for the restoration of full unity between the two lungs of European Christianity."[36]
References
- Citations
- Kinsman, Frederick Joseph (1924). Americanism and Catholicism. Longman. p. 203.
The one most talked about is the "Branch Theory," which assumes that the basis of unity is a valid priesthood. Given the priesthood, it is held that valid Sacraments unite in spite of schisms. Those who hold it assume that the Church is composed of Catholics, Eastern Orthodox, eastern heretics possessing undisputed Orders, and Old Catholics, Anglicans, Swedish Lutherans, Moravians, and any others who might be able to demonstrate that they had perpetuated a valid hierarchy. This is chiefly identified with High Church Anglicans and represents the survival of a seventeenth century contention against Puritans, that Anglicans were not to be classed with Continental Protestants.
- Avis, Paul (2018). The Oxford Handbook of Ecclesiology. Oxford University Press. ISBN 978-0-19-108138-5.
- Chapman, Mark David; Clarke, Sathianathan; Percy, Martyn (2016). The Oxford Handbook of Anglican Studies. Oxford University Press. ISBN 978-0-19-921856-1.
- Dragani, Anthony (2007). Adrian Fortescue and the Eastern Christian Churches. Gorgias Press LLC. p. 80. ISBN 9781593333454.
According to this theory, as Fortescue explains it, Christ's Church has no visible unity but is instead portioned into numerous denominations that are somehow invisibly connected. He asserts that this theory is common among all Protestant bodies, although each one generally holds that it is the purest branch. Fortescue considers the Anglican version unique, however, for it divides the Church into only three branches: the Eastern branch (Eastern Orthodoxy), the continental Westen branch (Roman Catholicism), and the British branch (Anglicanism).
- Evdokimov, Paul (2011). Orthodoxy. New City Press. p. 342. ISBN 9781565483699. Retrieved 28 March 2014. It is important to note that Evdokimov is not supporting the concept of "branch theory," but the opposite. From his point of view the Orthodox Church is complete in itself and the "Church" in the last sentence of this citation refers to it, not others.
- Knight, Dr Frances; Morgan-Guy, Dr John; Brown, Professor Stewart J. (2013). Religion, Identity and Conflict in Britain: From the Restoration to the Twentieth Century: Essays in Honour of Keith Robbins. Ashgate Publishing, Ltd. ISBN 978-1-4094-7222-3.
- Cunningham, Lawrence (2009-02-16). An Introduction to Catholicism. Cambridge University Press. p. 8. ISBN 9780521846073. Retrieved 28 March 2014.
This "branch" theory (i.e. one Catholic Church with three branches of Anglican, Orthodox, and Roman Catholic) has received mixed reception even within the Anglican Communion.
- Duffield, Gervase (1963). "The Church of England: Evangelical, Catholic, Reformed, and Protestant" (PDF). Churchman. Retrieved 15 May 2020.
- Dominus Iesus, 17 Archived April 11, 2013, at the Wayback Machine
- Letter of 16 September 1864 from the Holy Office to the Bishops of England (Denzinger, 1685 (old numbering)
- Modern culture runs risk of amnesia, from a speech given May 20th, 2010
- Zander, Lev (2003). "On the essence of ecumenical participation". In Plekon, Michael (ed.). Tradition alive : on the church and the Christian life in our time. Lanham: Rowman & Littlefield. pp. 230, 237. ISBN 0-7425-3162-7. Retrieved 2014-09-14.
- Palmer, William (1853). Dissertations on subjects relating to the "Orthodox" or "Eastern-Catholic Communion". London: J. Masters. p. 308. OCLC 2905982. Retrieved 2014-09-14. Quoted in Dragani, Anthony (2007). Adrian Fortescue and the Eastern Christian Churches. Gorgias dissertations. 19 (First Gorgias Press ed.). Piscataway, NJ: Gorgias Press. p. 81. ISBN 9781593333454. Retrieved 2014-09-14.
- Ware, Kallistos (29 April 1993). The Orthodox Church. Penguin Adult. pp. 246–247. ISBN 9780140146561. Retrieved 28 March 2014.
- Overbeck, J Joseph (1881). A plain view of the claims of the Orthodox Catholic Church as opposed to all other Christian denominations. London: Trübner. p. 112. OCLC 562257714. Retrieved 28 March 2014.
- Kallis, Anastasios (2003). "Orthodox Church". In Fahlbusch, Erwin; Bromiley, Geoffrey W. (eds.). The Encyclopedia of Christianity. 3. Grand Rapids: Wm. B. Eerdmans. p. 867. ISBN 978-0-8028-2415-8. Retrieved 2014-09-14.
- Fortescue, Adrian (1908) [1907]. The Orthodox Eastern Church (2nd ed.). London: Catholic Truth Society. p. 366. OCLC 880670516. Retrieved 2014-09-14.
- Gabel, Paul (2005). And God created Lenin: Marxism vs religion in Russia, 1917-1929. Amherst, NY: Prometheus. p. 35. ISBN 9781591023067. Retrieved 28 March 2014.
The Eastern Orthodox Church (Russian, Greek, Serbian, etc.) considered itself the One True Church. The Catholic Church to the west was a heresy, and Protestants were a heresy of a heresy.
- Kinnamon, Michael; Cope, Brian E. (31 December 1996). The Ecumenical Movement: An Anthology of Key Texts and Voices. WCC Publications. p. 484. ISBN 9780802842633. Retrieved 28 March 2014.
WCC was instrumental in promoting ecumenical consciousness at various international, regional and national levels, in countries of many Orthodox Churches. It was in this spirit during meetings of the WCC that Eastern Orthodox Churches and Oriental Churches have entered into an informal theological dialogue.
- Ustinov, Vitaly. "The ROCOR's Anathema Against Ecumenism (1983)". orthodoxinfo.com. Orthodox Christian Information Center. Archived from the original on 2014-07-02. Retrieved 2014-09-14.
- Epistle of His Eminence Archbishop Kyrill to the Flock of the Diocese of San Francisco and Western America on the Eve of the Regular Session of the Synod of Bishops. ROCOR: DIOCESE OF SAN FRANCISCO AND WESTERN AMERICA, 20 October 2006.
- Collinge, William J. (2012). Historical Dictionary of Catholicism. Scarecrow Press. p. 322. ISBN 978-0-81087979-9.
Today, it is recognized that the issues that divide Oriental Orthodox from Roman Catholics and Eastern Orthodox over Christology are largely verbal
- Prokurat, Michael; Peterson, Michael D.; Golitzin, Alexander (2010). The A to Z of the Orthodox Church. Scarecrow Press. p. 245. ISBN 978-1-46166403-1.
- Second Agreed Statement and Recommendations to the Churches. Geneva, Switzerland: Chambésy. 1990. ISBN 9782825413296.
- WCC, "Orthodox churches (Oriental)"
- The OCP Society, "The OCP Mission"
- Abraham, William J.; Kirby, James E. (2009-09-24). The Oxford Handbook of Methodist Studies. Oxford University Press. p. 420. ISBN 9780191607431. Retrieved 28 March 2014.
Whereas the Russian Methodist Church typically holds some variation of the 'branch theory' ecclesiology, advocating that Christianity is represented by three branches: Orthodox, Roman Catholic, and Protestant, Russian Orthodox theologians of all kinds staunchly reject the branch theory and insist that the Orthodox Church represents the Church of Christ on earth the entire fullness of the church that Christ established. These questions are important because they lay the ground for understanding in what way the United Methodist Church belongs to the church that Christ established on earth from the Orthodox point of view.
- Bruce, Frederick Fyvie; Rupp, Ernest Gordon (1968). Holy Book and Holy Tradition. Manchester University Press. p. 136.
- Robert F. Taft, "Perceptions and Realities in Orthodox–Catholic Relations Today"
- Jesuit Calls on Catholic and Orthodox Churches to Restore Communion"
- Michael Fahey, S.J. (1996). Orthodox and Catholic Sister Churches: East Is West and West Is East. Marquette University Press. ISBN 0-87462-576-9.
- Michael A. Fahey, "Am I My Sister's Keeper?" in America, 28 October 2000
- Andrii Krawchuk, Thomas Bremer (2014). Eastern Orthodox Encounters of Identity and Otherness: Values, Self-Reflection, Dialogue. Palgrave Macmillan. p. 7. ISBN 9781137377388.
Vatican II (1962-1965) was a key turning point that marked the beginning of Catholic ecumenism, paved the way for the current dialogue, and hammered out seminal ideas ("sister Churches" and "two lungs") about the nature and shape of that relationship within a new framework of mutuality. While the road to Catholic-Orthodox understanding has not always been smooth and numerous challenges still remain, the author argues that further ecumenical progress stands to gain from a new understanding of each church as diverse and multifaceted in its own right.
- Congregation for the Doctrine of the Faith, "Note on the expression 'Sister Churches'", 30 June 2000 Archived 1 April 2015 at the Wayback Machine
- Article "Orthodox-Roman Catholic dialogue and of the ideas of 'Sister Churches' or of the Churches as 'two lungs' of the Body as contemporary expressions of the despised 'branch theory' of ecclesiology" in Orthodox Life, Volumes 57-58, 2006, p. 26 ("sister churches")
- Alfeyev, Hilarion (25 September 2005). Can Europe breathe with one lung? Catholic-Orthodox dialogue today. Retrieved 28 March 2014.
Christianity must breathe with two lungs, Eastern and Western. This metaphor, which belongs to the Russian poet Vyacheslav Ivanov and derives from the worldview of Vladimir Soloviev, is very popular in Catholic circles. It was used by Pope John Paul II in his public addresses. Today, Ivanov's metaphor is often used with regard to Europe and European Christianity, as well as within the context of the dialogue between the Catholic and the Orthodox Churches.
- B.C. (2013-03-20). "Orthodox Christians and Catholics: one lung or two". economist.com (blog). London: The Economist. Archived from the original on 2013-03-20.
- Bird, Robert (2006). The Russian Prospero: the creative universe of Viacheslav Ivanov. Madison, WI: University of Wisconsin Press. p. 289. ISBN 9780299218300.
- John Paul II (1987-03-25). "Redemptoris Mater". vatican.va. n. 34. Archived from the original on 2015-02-04. Retrieved 2016-03-18.
- Kovacs, Nick. "Breathing with Two Lungs Again". Retrieved 29 March 2014.
Using Pope John Paul II's analogy, the left lung represents the Latin Rite, and the right lung represents the Eastern Churches. (Note to Viewers: The Eastern Churches include all of the Eastern Rites in union with Rome, and the separated Orthodox Churches.)
- Dragani, Anthony (14 September 2001). "Breathing with Both Lungs". Eternal Word Television Network. Retrieved 28 March 2014.
In the context of Ut Unum Sint, it becomes clear that the Holy Father is claiming that the Catholic Church has been dominated primarily by the Latin tradition. He believes that a balance must be restored, in which both the Latin and Eastern traditions will contribute to the health of the Church.
- Cunningham, Lawrence (2009). "The many meanings of Catholicism". An introduction to Catholicism. Introduction to religion. Cambridge [u.a.]: Cambridge University Press. p. 15. ISBN 978-0-52184607-3.
- Faris, John D. (2000). "An overview of the Code of Canons of the Eastern Churches". In Beal, John P.; et al. (eds.). New commentary on the Code of Canon Law. New York [u.a.]: Paulist Press. p. 27. ISBN 9780809105021.
- Rigali, Justin (2006). "The Eastern Churches: East and West together in the Church". Reliving Vatican II: it's all about Jesus Christ. Chicago, IL: Archdiocese of Chicago. Liturgy Training Publications. p. 39. ISBN 978-1-56854597-4.
- Anonymous (unsigned) (May–June 2007) [Composed in 2004]. "Ecumenism" (PDF). Orthodox Life. Vol. 58 no. 3. p. 26. ISSN 0030-5820. Archived (PDF) from the original on 2013-12-19. Retrieved 2016-03-18.
- Phillips, Andrew. "Restoring the spiritual unity of Europe". Colchester, Essex: St John's Russian Orthodox Church. Retrieved 28 March 2014.
For this reason the present Pope John Paul II has spoken rather of the 'two-lung theory', an idea which has much appeal to a Pope from Eastern Europe who lives in Western Europe. He seems to have used this expression for the first time in his Apostolic Letter Euntes in mundum in 1988 on the millennium of the Baptism of Ancient Russia: 'Europe has two lungs, it will never breathe easily until it uses both of them'. This metaphor has since often been used by his speechwriters, such as the French philosopher Olivier Clement, who frequents both Greek Orthodox and Roman Catholic churches. However attractive the idea of uniting East and West, Orthodoxy and Catholicism, just as two lungs are united in one body, this theory is unacceptable to the vast majority of Orthodox and also to more than a few Roman Catholics.Firstly, it is unacceptable because it presents the Church as having two parts, a Western part, Catholicism, and an Eastern part, Orthodoxy. It presents therefore a territorialist concept, that Orthodoxy is only for Easterners, and that Catholicism is only for Westerners. Church unity is all a mere matter of geography and culture. This is obviously not the case, since there are Easterners who at present find a spiritual home in Catholicism, and Westerners who find a spiritual home in Orthodoxy. Secondly, the metaphor is untrue because the Church is not composed of parts of a body, two lungs, but of a single body, in fact, the Church is the Body of Christ, as the Apostle Paul called it in the first century. If the Church were two lungs, what would the heart or the stomach or the legs or the brain or any other organs or members represent? Either the Church is Roman Catholicism or else it is Orthodoxy.
- Horga, Ioan; Brie, Mircea (2003). "Religion in the context of secularization and globalization". In Marczewska-Rytko, Maria (ed.). Religion in a Changing Europe. Lublin, PL: Maria Curie-Skłodowska University Press. p. 32. ISBN 8322720890. Retrieved 28 March 2014.
- Bria, Ion (1991). The Sense of Ecumenical Tradition: The Ecumenical Vision and Witness of the Orthodox. WCC Publications, World Council of Churches. ISBN 9782825409664. Retrieved 28 March 2014.
Emphasis on the spirit of catholicity or universality as communion in the Spirit questions the validity of the Roman Catholic theory of 'the two lungs'.