There are three kinds of ‘chair’ – the royal chair, or throne, 2 Sam. 23:8: ‘David sitting in the chair, etc.'; the priestly chair, 1 Kings 1:9: ‘Now Eli the priest was sitting on a stool before the door of the temple of the Lord'; and the magisterial or professorial chair, Matt. 23:1: ‘The scribes and the Pharisees have sat on the chair of Moses.’ Peter sat on the royal chair because he was first among all kings; on the priestly chair because he was the shepherd of all clerics; and on the magisterial chair because he was the teacher of all Christians.
The Church commemorates the Chair of St. Peter with a feast day because blessed Peter is said to have been raised on this day to the seat of honour in Antioch. There appear to be four reasons for the institution of this solemnity. The first is that when blessed Peter was preaching in Antioch, Theophilus, governor of the city, said to him: ‘Peter, why are you corrupting my people?’ Peter then preached the faith of Christ to Theophilus, who immediately had him imprisoned and deprived of food and drink. The apostle was almost exhausted but regained some strength, turned his eyes to heaven, and said: ‘Christ Jesus, helper of the helpless, come to my aid! These trials have almost destroyed me!’ The Lord answered him: ‘Peter, did you think I had deserted you? You impugn my kindness when you are not afraid to say such things against me! The one who will relieve your misery is at hand!’
Meanwhile Saint Paul heard of Peter’s imprisonment. He presented himself to Theophilus, asserted that he was highly skilled in many arts and crafts, and said that he knew how to sculpt in wood and stone and could do many other kinds of work as well. Theophilus pressed him to stay on as a member of his household. A few days later Paul went secretly to Peter in his cell and found him very weak and almost dead. Paul wept bitterly and took Peter in his arms, weeping profusely, and burst out: ‘O my brother Peter, my glory, my joy, the half of my soul, now that I am here you must recover your strength!’ Peter opened his eyes, recognized Paul, and began to cry but could not speak. Paul quickly opened the other’s mouth, forced food into him, and thus got some warmth into his body. The food strengthened Peter, who threw himself into Paul’s embrace and both of them shed a flood of tears.
Paul left the jail cautiously and went back to Theophilus, to whom he said: ‘O good Theophilus, great is your fame, and your courtliness is the friend of honour. But a small evil counteracts your good! Think about what you have done to that worshiper of God who is called Peter, as if he were someone of importance! He is in rags, misshapen, reduced to skin and bones, a nobody, notable only for what he says. Do you think it is right to put such a man in jail? If he were enjoying the freedom to which he is accustomed, he might be able to do you some useful service. For instance, some say that he restores the sick to health and the dead to life!’ Theophilus: ‘Idle tales, Paul, idle tales! If he could raise the dead, he would free himself from prison!’ Paul: ‘Just as his Christ rose from the dead (or so they say) yet would not come down from the cross, so Peter, following Christ’s example (it is said), does not set himself free and is not afraid to suffer for Christ!’ Theophilus: ‘Tell him, then, to bring my son, who has been dead for fourteen years, back to life, and I will release him unharmed and free!’ Paul therefore went to Peter’s cell and told him he had solemnly promised Theophilus that his son would be brought back to life. ‘That’s a hard promise to keep, Paul,’ said Peter, ‘but God’s power will make it easy!’ Peter was taken out of prison and led to the tomb. He prayed, and the governor’s son came to life immediately.
There are some things here, however, that sound improbable, for instance, that Paul would pretend that he had the natural skills needed to do and make a variety of things, or that the son’s sentence of death was suspended for fourteen years. But however that may be, Theophilus and the whole population of Antioch, together with a great many other people, believed in Christ. They built a magnificent church and erected an elevated throne in the center, to which they lifted Peter up so that he could be seen and heard by everybody. He occupied that chair for seven years, but afterwards went to Rome and ruled the see of Rome for twenty-five years. The Church, however, celebrates this first honour because it was the beginning of the custom by which bishops are distinguished by place, power, and name. Thus what we read in Ps. 106:32 is fulfilled: ‘Let them exalt him in the church of the people, and praise him in the chair of the ancients.’
– Jacobus de Voragine, Legenda Aurea
(trans. William Granger Ryan)
Perhaps I’ll post the other three reasons ‘for the institution of this solemnity’ later [for instance, next year].