Today, the Latin-rite liturgy celebrates the Feast of the Chair of St Peter. This is a very ancient tradition, proven to have existed in Rome since the fourth century. On this day we give thanks to God for the mission he entrusted to the Apostle Peter and his Successors.

What was the "Chair" of St Peter? Chosen by Christ as the "rock" on which to build the Church, he began his ministry in Jerusalem, after the Ascension of the Lord and Pentecost. The Church's first "seat" was the Upper Room. Subsequently, the See of Peter was Antioch, a city which at the time was the third metropolis of the Roman Empire after Rome and Alexandria in Egypt. Peter was the first Bishop of that city, which was evangelized by Barnabas and Paul. From there, Providence led Peter to Rome.

—The See of Rome came to be recognized as the See of the Successor of Peter, and its Bishop's "cathedra" represented the mission entrusted to him by Christ to tend his entire flock: it as a privileged sign of the love of God, the eternal Good Shepherd.