. . . the Church had its solemn beginning with the descent of the Holy Spirit. In this extraordinary event we find the essential and qualifying marks of the Church: the Church is one, like the community of Pentecost, which was united in prayer and “of one mind”: “it had but one heart and one soul” (Acts 4:32).
The Church is holy, not because of its own merits, but because, animated by the Holy Spirit, it keeps its gazed fixed upon Christ to become conformed to him and his love. The Church is catholic because the Gospel is destined for all people and for this reason, already at the beginning, the Holy Spirit gives the Church the ability to speak in different tongues. The Church is apostolic because, built upon the foundation of the apostles, it faithfully conserves their teaching through the uninterrupted chain of apostolic succession.
The Church, moreover, is missionary by its nature, and from the day of Pentecost the Holy Spirit does not cease to move it along the roads of the world to the ends of the earth and to the end of time. This reality, which we can verify in every epoch, is already anticipated in the Book of Acts, in which the passage of the Gospel from the Jews to the pagans, from Jerusalem to Rome, is described.
Rome represents the pagan world and therefore all peoples who are outside the ancient people of God. In fact, the Acts conclude with the arrival of the Gospel in Rome. We can say, then, that Rome is the concrete name of the catholicity and missionary spirit of the Church; it expresses fidelity to the origins, to the Church of all times, to a Church that speaks in all languages and goes out to meet every culture.
Dear brothers and sisters, the first Pentecost happened when Mary Most Holy was present among the disciples in the cenacle in Jerusalem and prayed. Today also we entrust ourselves to her maternal intercession so that the Holy Spirit descend abundantly upon the Church of our time and fill the hearts of all the faithful and enkindle in them — in us — the fire of his love.
Pope Benedict XVI on the Solemnity of Pentecost. May 27, 2007.