Week of Prayer for Christian Unity

The Week of Prayer for Christian Unity is an international Christian ecumenical observance kept annually between 18 January and 25 January. It is an octave, that is, an observance lasting eight days.

The Week of Prayer for Christian Unity began in 1908 as the Octave of Christian Unity, and focused on prayer for church unity. The dates of the week were proposed by Father Paul Wattson, cofounder of the Graymoor Franciscan Friars. He conceived of the week beginning on the Feast of the Confession of Peter, the Protestant variant of the ancient Feast of the Chair of Saint Peter, on 18 January, and concluding with the Feast of the Conversion of Saint Paul on 25 January.

Pope Pius X officially blessed the concept, and Benedict XV "encouraged its observance throughout the entire Roman Catholic Church." For a while, the observance was renamed the "Chair of Unity Octave" by Wattson, in order to emphasize the relationship between Christian unity and the Petrine See (i.e., the papacy).

Protestant leaders in the mid-1920s also proposed an annual octave of prayer for unity amongst Christians, leading up to Pentecost Sunday (the traditional commemoration of the establishment of the Church).

Abbé Paul Couturier of Lyons, France, who has been called "the father of spiritual ecumenism", had a slightly different approach from that of Father Wattson, a convert to Roman Catholicism from Anglicanism. He advocated prayer "for the unity of the Church as Christ wills it, and in accordance with the means he wills", thereby enabling other Christians with differing views of the Petrine ministry to join in the prayer. In 1935, he proposed naming the observance "Universal Week of Prayer for Christian Unity", a proposal accepted by the Catholic Church in 1966. Father Couturier's message influenced a Sardinian nun, Blessed Sister Maria Gabriella of Unity, whose deep, prayerful, sacrificial devotion to the cause of unity is held up by Rome as an example to be followed.

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