Bishops of the Church must go to Rome every five years for the "Ad Limina Apostolorum" visit, which is Latin for "To the threshold of the apostles." The apostles referred to are St. Peter and St. Paul, who were martyred in that city. The bishops go in groups by country or regions of their countries. During this visit, the bishops meet with the Holy Father, the successor of St. Peter, and share information about their dioceses.

However, the main purpose of these visits is to bring the bishops regularly to visit the tombs of the two pillars of the Church and pray before their relics. The bishops make this pilgrimage to sustain and deepen their faith, to draw themselves closer to the Lord. This pilgrimage to the heart of the Church renews the bishops' faith as successors of the apostles.

Turning to our Gospel reading, one day in Caesarea Philippi, when the disciples were still unsure of the Lord's divine identity, he asked them who they thought he was. St. Peter correctly answers, "You are the Christ, the Son of the living God." The Lord tells him that this answer was a divine inspiration.

St. Peter was the only apostle to whom the Lord gave a new name. This happened at the first meeting of the Lord and St. Peter, whose original name was Simon. St. John tells us that Andrew, Simon's brother, met the Lord first. Then he brought Simon to introduce him to the Lord. “Jesus looked at him and said, ‘You are Simon the son of John; you will be called Cephas’ (which is translated Peter).” Cephas is a word in Aramaic, the language they speak. It was translated into Greek, the language in which the gospels were written, as Petros, which means rock. 

The name change has great significance. In the Old Testament, a name change usually preceded the commissioning of a mission. Pope Benedict said that the name Peter is not just a name but a mandate that this apostle received from the Lord. This is what the Lord tells him in Caesarea Philippi: “And so I say to you, you are Peter, and upon this rock I will build my Church, and the gates of the netherworld shall not prevail against it. I will give you the keys to the Kingdom of heaven. Whatever you bind on earth shall be bound in heaven; and whatever you loose on earth shall be loosed in heaven.”

With three images the Lord makes very clear the mission of St. Peter: rock, keys, and to bind and to loose. Pope Benedict wrote about it: “Peter will be the rocky foundation on which he will build the edifice of the Church; he will have the keys of the Kingdom of Heaven to open or to close it to people as he sees it fit; lastly, he will be able to bind or to loose, in the sense of establishing or prohibiting whatever he deems necessary for the life of the Church.”

Now, let’s consider St. Paul. After the Lord in the New Testament, we learn the most about St. Paul. St. Paul was not one of the 12 apostles. The Lord personally called him about six years after his Ascension into Heaven. St. Paul dedicated himself to bringing the Gospel beyond the people of Israel to the Gentiles.

Saints Peter and Paul are, rightly called, the "indispensable" persons of the Church. These two, each in their own place, built the Church. These two great apostles are seen as one, which is why the Church associates them together. For example, their feast day is celebrated together and in the litanies of the saints they are named together.

Today, on the solemnity of these two greatest apostles, the universal Church gives glory to God for having given them to us as the most exemplary spiritual guides, shepherds, and teachers. Today, we also humbly ask the Lord, through their intercession, to grant us some of the virtues that adorned St. Peter and St. Paul.