Pope Benedict XVI said today that achieving Christian unity requires more than “cordiality and cooperation” and that it must be accompanied by interior conversion.

“Faith in Christ and interior conversion, both individual and communal, must constantly accompany our prayer for Christian unity,” said the Pope to over 8,000 pilgrims gathered in the Vatican’s Paul VI Audience Hall on Jan. 18.

The Pope’s comments mark the start of the 2012 Week of Prayer for Christian Unity that runs until Jan. 25. It will be observed by over 300 Christian churches and ecclesial communities around the globe. 

The Pope asked for “the Lord in a particular way to strengthen the faith of all Christians, to change our hearts and to enable us to bear united witness to the Gospel.”

In this way, he said, they “will contribute to the new evangelization and respond ever more fully to the spiritual hunger of the men and women of our time.”

The Pope explained that the concept of a week of prayer for Christian unity was initiated in 1908 by Paul Wattson, an Episcopalian minister from Maryland. One year later, he became a Catholic and was subsequently ordained to the priesthood.

Pope Benedict recalled how the initiative was supported by his predecessors Pope St. Pius X and Pope Benedict XV.  It was then “developed and perfected” in the 1930s by the Frenchman Abbé Paul Couturier, who promoted prayer “for the unity of the Church as Christ wishes and according to the means he wills.”

The mandate for the week of prayer, the Pope underscored, comes from the wish of Christ himself at the Last Supper “that they may all be one.” He observed that this mission was given a particular impetus by the Second Vatican Council (1962-65) but added that “the unity we strive for cannot result merely from our own efforts.” Rather,  “it is a gift we receive and must constantly invoke from on high.”  

The theme for 2012 Week of Prayer – “All shall be changed by the victory of Jesus Christ our Lord” – was crafted by the Polish Ecumenical Council. Pope Benedict said it reflects “their own experience as a nation,” which stayed faithful to Christ “in the midst of trials and upheavals,” including years of occupation by the Nazis and later the Communists.

The Pope tied the victory the Polish people experienced over their oppressors to overcoming the disunity that marks Christians.

He said that the “unity for which we pray requires inner conversion, both shared and individual,” and it cannot be “limited to cordiality and cooperation.” Instead, Christians must accept “all the elements of unity which God has conserved for us.”

Ecumenism, the Pope stated, is not an optional extra for Catholics but is “the responsibility of the entire Church and of all the baptized.” Christians, he said, must make praying for unity an “integral part” of their prayer life, “especially when people from different traditions come together to work for victory in Christ over sin, evil, injustice and the violation of human dignity.”

Pope Benedict then touched on the lack of unity in the Christian community, which he said “hinders the effective announcement of the Gospel and endangers our credibility.” Evangelizing formerly Christian countries and spreading the Gospel to new places will be “more fruitful if all Christians together announce the truth of the Gospel and Jesus Christ, and give a joint response to the spiritual thirst of our times,” he explained.

The Pope concluded his comments with the hope that this year’s Week of Prayer for Christian Unity will lead to “increased shared witness, solidarity and collaboration among Christians, in expectation of that glorious day when together we will all be able to celebrate the Sacraments and profess the faith transmitted by the Apostles.”

The general audience finished with Pope Benedict addressing pilgrims in various languages, including  greeting a group of men and women from the U.S. Navy and Marine Corps, before leading the crowd in the Our Father and imparting his apostolic blessing.