Usually feast days celebrate a person or an action of God, but today we celebrate the Chair of St Peter. This is not really the feast day for a chair, though a much restored and enhanced Chair of St Peter indeed exists. It was originally made of acacia, but later rebuilt with oak and iron and decorated with icons and plaques.
This feast day celebrates the abiding divine guidance of the Church. It is a very old feast day in the Church, going back to at least the Fourth Century. We have, for example, the letter of St Jerome, who lived from around 347 to 426, to the Bishop of Rome. Here he explains his reverence for St Peter and his successors:
I decided to consult the chair of Peter, where that faith is found exalted by the lips of an Apostle…. I follow no leader save Christ, so I enter into communion with your beatitude, that is, with the chair of Peter for this I know is the rock upon which the Church is built!
This feast first of all celebrates the Gospel account of Jesus’ commission to Peter to found a Church and to care for all his lambs and all his sheep. Secondly, it celebrates the unity of the Church under Peter and God’s promise to guide for the Church. Thirdly, it reminds us to be like St Jerome, and to have the wisdom to acknowledge that we may not know everything. The tradition of the Church, centred on the Chair of St Peter, should be respected and heeded, because there God’s hand is certainly at work.