From the papal homily on the feast of Sts. Peter and Paul (from zenit):
….By virtue of their martyrdom, Peter and Paul are in reciprocal relationship forever. A favorite image of Christian iconography is the embrace of the two apostles on the way to martyrdom. We can say that their martyrdom itself, in its deepest reality, is the realization of a fraternal embrace. They die for the one Christ and, in the witness for which they give their lives, they are one. In the writings of the New Testament, we can, so to speak, follow the development of their embrace, this unity in witness and in mission.
Everything starts when Paul, three years after his conversion, goes to Jerusalem “to consult Cephas” (Galatians 1:18). Fourteen years later, he again goes up to Jerusalem to explain “to the most esteemed persons” the Gospel that he preaches in order so that he might not run the risk of “running, or having run, in vain” (Galatians 2:1f). At the end of this meeting, James, Cephas and John give him their right hands, thus confirming the communion that unites them in the one Gospel of Jesus Christ (Gal 2:9). A beautiful sign of this growing interior embrace, which develops despite the difference in temperaments and in tasks, I find in the fact that the co-workers mentioned at the end of the First Letter of St. Peter — Silvanus and Mark — were equally close co-workers of St. Paul. This having of the same co-workers makes the communion of the one Church, the embrace of the great apostles, visible in a very concrete way.
Peter and Paul met each other at least twice in Jerusalem; at the end their paths take them to Rome. Why? Was this perhaps more than just pure chance? Is there perhaps a lasting message in it? Paul arrived in Rome as a prisoner, but at the same time as a Roman citizen who, after his arrest in Jerusalem, as a Roman citizen appealed to the emperor, to whose tribunal he was brought. But in a more profound sense, Paul came to Rome voluntarily. Through the most important of his letters, he had already drawn close to this city interiorly: to the Church in Rome, he had addressed the writing which, more than any other, is the synthesis of his whole proclamation and his faith. In the opening salutation of the letter, he says that the whole world speaks of the faith of the Christians of Rome and that this faith, therefore, was known everywhere as exemplary (Romans 1:8). And then he writes: “I do not want you to be unaware, brothers, that I often planned to come to you, though I was prevented until now” (1:13). At the end of the letter he comes back to this theme, now speaking of a plan to travel to Spain. “When I go to Spain I hope to see you when I pass through and to be helped by you on my way to that region, after having enjoyed your presence for a little while” (15:24). “And I know that, having come to you, I shall come in the fullness of Christ’s blessing” (15:29). There are two things made evident here: Rome is for Paul a stage on the way to Spain, that is — according to his conception of the world — towards the extreme end of the earth. He considers his mission to be the fulfillment of the task received from Christ, the bringing of the Gospel to the very ends of the world. Rome is along this route. While Paul usually only goes to places where the Gospel had not yet been announced, Rome is an exception. There he finds a Church whose faith the world speaks about. Going to Rome is part of the universality of his mission as one sent to all peoples. The way to Rome, which, already before his external trip, he had traveled interiorly with his letter, is an integral part of his task of bringing the Gospel to all peoples — of founding the Church, catholic and universal. Going to Rome is for him the expression of his mission’s catholicity. Rome must make the faith visible to the whole world, it must be the meeting place in the one faith.
But why did Peter go to Rome? About this the New Testament does not say anything directly. But it gives us some indication. The Gospel of St. Mark, which we may consider a reflection of the preaching of St. Peter, is intimately oriented towards the moment when the Roman centurion, facing the death of Christ on the cross, says, “Truly this man was the Son of God!” (15:39). At the cross the mystery of Jesus Christ is revealed. Beneath the Cross the Church of the gentiles is born: the centurion of the Roman execution squad recognizes the Son of God in Christ. The Acts of the Apostles describe the episode of Cornelius, the centurion of the Italic cohort, as a decisive stage for the entrance of the Gospel into the pagan world. Following a command of God, he sends someone to get Peter, and Peter, also following a divine order, goes to the centurion’s house and preaches. While he is speaking, the Holy Spirit descends on the gathered domestic community and Peter says: “Can anyone withhold the water for baptizing these people, who have received the holy Spirit even as we have?” (Acts 10:47).
Thus, in the Council of the Apostles, Peter becomes the intercessor for the Church of the pagans who do not need the Law because God “has purified their hearts with faith” (Acts 15:9). Certainly, in the Letter to the Galatians, Paul says that God gave strength to Peter for the apostolic ministry among the circumcised, and to Paul himself, the ministry among the pagans instead (Gal 2:8). But this assignment could be in force only as long as Peter remained with the 12 in Jerusalem in the hope that all of Israel would adhere to Christ. In the face of later developments, the 12 recognized the time in which they too must go forth into the world to announce the Gospel to it. Peter who, following divine order, had been the first to open the door to pagans, now leaves the leadership of the Christian-Jewish Church to James the Less, in order to dedicate himself to his true mission: to the ministry of the unity of the one Church of God made up of Jews as well as pagans. The desire of Paul to go to Rome highlights above all, as we have seen, the word “catholica” [“catholic”] among the characteristics of the Church.
St. Peter’s journey to Rome, as representative of the peoples of the world, is above all associated with the word “una” [“one”]: he has the task of creating the “unity” of the “catholica,” of the Church made up of Jews and pagans, the Church of all peoples. And this is the permanent mission of Peter: to make sure that the Church never identifies herself with any one nation, any one culture or any one state. That it may always be the Church of all. That it may unite mankind beyond every frontier and, amidst the divisions of this world, make God’s peace present, the reconciling power of his love. Due to technology that is now the same everywhere, due to the global information network, and due also to the linking of common interests, there are new modes of unity in the world, which have caused the explosion of new oppositions and given new impetus to old ones. In the midst of this external unity, based on material things, we have all the more need of interior unity which comes from the peace of God – the unity of all those who, through Jesus Christ, have become brothers and sisters. This is the permanent mission of Peter, as well as the special task entrusted to the Church of Rome….