Here’s a translation (scroll down)
Today, we solemnly honor Saints Peter and Paul, “apostles of Christ, pillars and foundation of the city of God,” as sung in today’s liturgy . Their martyrdom was considered as the true and proper birth of the Church of Rome.
The two Apostles rendered their supreme testimony for Christ not far apart in time and space: here in Rome, St. Peter was crucified, and shortly thereafter, St. Paul was beheaded.
Their blood thus mingled together almost as a single witness for Christ, which impelled St. Irinaeus, Bishop of Lyons, in the middle of the second century, to speak of the “Church founded and constituted in Rome by the two most glorious apostles Peter and Paul (Against Heresy 3,3,2).
A little time later, from northern Africa, Tertullian exclaimed: “This Church of Rome, how blessed it is! It was the Apostles themselves who, with their blood, poured forth all there was to know of the doctrine“ (The Prescription Against Hereticsm 36).