Strangers have become friends; crossing every border, we recognize one another as brothers and sisters. This brings to fulfilment the mission of St Paul, who knew that he was the “minister of Christ Jesus among the Gentiles, with the priestly duty of preaching the Gospel of God so that the Gentiles [might] be offered up as a pleasing sacrifice, consecrated by the Holy Spirit” (Rom 15: 16). The purpose of the mission is that humanity itself becomes a living glorification of God, the true worship that God expects: this is the deepest meaning of catholicity – a catholicity that has already been given to us, towards which we must constantly start out again. Catholicity does not only express a horizontal dimension, the gathering of many people in unity, but also a vertical dimension: it is only by raising our eyes to God, by opening ourselves to him, that we can truly become one.
Like Paul, Peter also came to Rome, to the city that was a centre where all the nations converged and, for this very reason, could become, before any other, the expression of the universal outreach of the Gospel. As he started out on his journey from Jerusalem to Rome, he must certainly have felt guided by the voices of the prophets, by faith and by the prayer of Israel.
The mission to the whole world is also part of the proclamation of the Old Covenant: the people of Israel were destined to be a light for the Gentiles. The great Psalm of the Passion, Psalm 22, whose first verse Jesus cried out on the Cross: “My God, my God, why have you forsaken me?”, ends with the vision: “All the ends of the earth shall remember and turn to the Lord; all the families of the nations shall bow down before him” (Ps 22: 28). When Peter and Paul came to Rome, the Lord on the Cross who had uttered the first line of that Psalm was risen; God’s victory now had to be proclaimed to all the nations, thereby fulfilling the promise with which the Psalm concludes.
Catholicity means universality – a multiplicity that becomes unity; a unity that nevertheless remains multiplicity. From Paul’s words on the Church’s universality we have already seen that the ability of nations to get the better of themselves in order to look towards the one God, is part of this unity. In the second century, the founder of Catholic theology, St Irenaeus of Lyons, described very beautifully this bond between catholicity and unity and I quote him. He says: “The Church spread across the world diligently safeguards this doctrine and this faith, forming as it were one family: the same faith, with one mind and one heart, the same preaching, teaching and tradition as if she had but one mouth. Languages abound according to the region but the power of our tradition is one and the same. The Churches in Germany do not differ in faith or tradition, neither do those in Spain, Gaul, Egypt, Libya, the Orient, the centre of the earth; just as the sun, God’s creature, is one alone and identical throughout the world, so the light of true preaching shines everywhere and illuminates all who desire to attain knowledge of the truth” (Adv. Haer. I 10, 2). The unity of men and women in their multiplicity has become possible because God, this one God of heaven and earth, has shown himself to us; because the essential truth about our lives, our “where from?” and “where to?” became visible when he revealed himself to us and enabled us to see his face, himself, in Jesus Christ. This truth about the essence of our being, living and dying, a truth that God made visible, unites us and makes us brothers and sisters. Catholicity and unity go hand in hand. And unity has a content: the faith that the Apostles passed on to us in Christ’s name.