Ecumenism is, principally, dialogue between Christian denominations aimed at promoting the restoration of unity among all Christians through understanding, through mutual respect and toleration, and through practical cooperation in areas of common concern, such as care for the poor, sick, and needy.
Orthodox Christians take widely different attitudes toward ecumenism. A few embrace the Anglican "branch theory" which holds that the various divisions in Christianity all represent branches of the same Church just as the branches of a tree are all integrally part of the same living tree. Many Orthodox Christians object to this theory on the ground that it is inconsistent with properly Orthodox ecclesiology. It tends to minimize Orthodoxy and reduces its stature from exclusively the one, holy, catholic, and apostolic Church to that of a relatively small segment of the Church: one denomination among many.
However, one may dispute the branch theory and still support ecumenical activity to a point. Some Orthodox Christians regard ecumenism as an opportunity to present Orthodoxy to the world as a unique witness to the ancient Christian faith and to the Church as the indivisible body of Christ. Others feel that ecumenism necessarily undermines this witness and feel that the Orthodox will be forced to alter traditional practices and even the very content of the ancient apostolic faith.
In the Twentieth Century particularly, some ecumenical activities have drawn sharp criticism from various voices within the Orthodox Church, particularly participation in the World Council of Churches and, in the United States, the National Council of Churches. Ecumenism is often opposed by Traditionalists, particularly those in Old Calendarist jurisdictions, who regard the New Calendar as a symptom of ecumenism.
One of the more controversial documents drawn up in recent years pertaining to ecumenism is the Balamand Statement, an unofficial joint document of recommendation on Uniatism signed by representatives of the Orthodox Church and the Roman Catholic Church in 1993.
- Ecumenical Guidelines for SCOBA
- Baptism and "sacramental economy": An agreed statement of the North American Orthodox-Catholic Theological Consultation - Saint Vladimir's Orthodox Seminary, Crestwood, New York - June 3, 1999
- Ecumenism: Origins - Expectations - Disenchantment, September 2004 Conference on Ecumenism, held at Aristotle University, Thessaloniki, Greece
- Conclusions of the Conference on Ecumenism
- The Church of Serbia vis-à-vis Ecumenism, by Bishop Artemije of Raska and Prizren
- Contours of Conversion and the Ecumenical Movement, by Hieromonk Alexis (Trader) of Karakallou
- The Consequences of Orthodox Participation in the Ecumenical Movement on the Orthodox Witness to the Heterodox West, by Fr. John Reeves
- The Mystery of Baptism and the Unity of the Church, by Fr. Peter A. Heers