Although prayer is certainly at the heart of Christian life, praying together is not an easy exercise for churches within worldwide Christendom.
Even today, common prayers are exceptional events rather than part of the daily life of the churches. But at least once a year it has become "normal" for many churches and congregations to pray together during the annual celebration of the Week of Prayer for Christian Unity.
In 2008, the 100th anniversary of this most meaningful ecumenical initiative is being celebrated around the globe.
The roots of the Week of Prayer for Christian Unity can be traced back to the beginning of the 19th century.
Initiatives involving praying for unity together with Christians from other denominations had been taking place here and there for over a century when, in 1908, a priest and a sister, both Episcopalians, publicly celebrated for the first time an Octave of Prayer for Church Unity from 18-25 January in Graymoor, Garrison, New York.
The Rev Paul Wattson and Mother Lurana White, co-founders of a small religious community in the Franciscan tradition known as the Society of the Atonement, chose for the octave the days spanning from what was at that time in the Roman Catholic calendar the "feast of the Chair of Peter", to the "feast of the conversion of Paul".
In celebrating its 100th anniversary, this year's Week of Prayer for Christian Unity points to that historical milestone as its foundational moment. But it is clear that a lot has changed in the ecumenical landscape over the last century.
The Octave of Prayer for Church Unity of those days was based on a concept of unity as re-union of Christendom under the Pope's authority. For that reason, the octave was neither appealing nor theologically acceptable for Christians and churches outside the Roman Catholic Church, except for some Anglicans who were sympathetic to the idea of a reunion of Canterbury with Rome – like Wattson and White, who joined the Roman Catholic Church themselves.
While it soon became widely observed in the Roman Catholic Church, the octave was by no means the only initiative of prayer for church unity at that time.
Well before 1908, the World Evangelical Alliance, the World Student Christian Federation, the Young Men's Christian Association together with the Young Women's Christian Association, had already all launched worldwide annual weeks or days of prayer in which the aspect of unity played an important role.
