Benedict presided at a prayer service in St. Paul Outside the Walls Basilica in Rome to mark the end of a week of prayer dedicated in churches around the world to efforts aimed at uniting Christians.

"Honest and loyal dialogue constitutes the typical and indispensable instrument in the search for unity," Benedict said.

Christians were praying "so that all the disciples of Christ be one, and so ... they can give harmonious testimony to the men and women of our times," said Benedict, who is devoting much of his papacy to achieving Christian unity. ...