The Pope called the faithful to a greater commitment to Christian unity during Wednesday's audience. The "peace and harmony" of Christians, he said, shows the world an "authentic" witness to the Gospel message.
At the end of Wednesday morning's audience in St. Peter's Square, Pope Benedict drew attention to the concurrent plenary meeting of the Joint International Commission for Theological Dialogue between the Catholic Church and the Orthodox Church.
The meeting is taking place in Vienna, Austria this week, with participants examining "the role of the Bishop of Rome in the communion of the Universal Church," particularly in the first millennium of Christianity.
Of this, the Holy Father said, "obedience to the will of the Lord Jesus and consideration for the great challenges facing Christianity today, oblige us to commit ourselves seriously to the cause of re-establishing full communion among the Churches.
"I exhort everyone to intense prayer for the work of the commission and for the ongoing development and consolidation of peace and harmony among the baptized, that we may show the world an increasingly authentic evangelical witness."