Today we honor the great saints, Peter and Paul. They had met only briefly in their lifetimes, but we honor them together because they both died in Rome after founding the Church there.
In the year 180 St. Irenaeus looked back on that joint role of Peter and Paul In implanting the teaching of Christ in Rome.
Let me switch for a moment to the story of Irenaeus. He had been serving as the bishop of Lyons in France when the pope asked him to come to Rome to deal with a new kind of Christians called Gnostics. The Gnostics were claiming to have new gospels dictated to them by angels.
Irenaeus went to Rome, and instead of arguing with the Gnostics, he took to attending their gatherings, taking notes on all their new teachings. Having made friends with them by his openness, he gradually brought them around to seeing why the pope differed from them.
Mainly, Irenaeus had them recalling something St. Paul had written to the Galatians, namely, “Even if an angel from heaven should preach to you a gospel other than the one we preached to you, let that one be accursed.”
In that year 180 when Irenaeus was writing these things, the Christians in France, Spain, Alexandria still had old people who had listened to the preaching of one or another of the twelve apostles who had settled in their countries.
Irenaeus told the Gnostics that if they wanted to hear the genuine teachings of Jesus, they should go to those early churches founded by Apostles. He said that the bishops in those places held firm to the teaching they had received from the Apostles.
Irenaeus went on then to say, “Since it would be very tedious to reckon up the succession of all the churches, we will indicate that tradition derived from the apostles of the very great, the very ancient, and universally known church founded and organized in Rome by the two most glorious apostles, Peter and Paul. It is a matter of necessity that every church should agree with this church.”
So, in honoring Peter and Paul together we are thanking them for handing on the true teachings of Jesus.