21st Sunday 2026
Isaiah 22:15, 19-23; Romans 11:33-36; Matthew 16: 13-20
When did you last open or close your car door by inserting a key in a lock and turning it? You can’t remember, can you? It was so long ago. Now you simply point the fob, press a button, and Bob’s your uncle.
Or on holiday, when did you open your room door with a key, rather than one of those plastic rectangles, which you spend half an hour attempting to manoeuvre into the exact spot, before giving up in dismay and heading off to summon assistance? I imagine that, in twenty years at the most, keys will be as obsolete as mangles and dolly tubs.
For millennia, keys have been indispensable in practical terms, but have also had a ceremonial value as a symbol of authority. According to Isaiah, “The Key of the House of David” was to be placed on the shoulder of the steward. It wouldn’t be much practical use there, but would serve as a visible sign of his status for all to see.
Similarly, the bestowal on Peter of the “Keys of the Kingdom of Heaven”—metaphorical keys, of course, rather than pieces of metal—symbolised his authority as leader of the Church, an authority which we believe to have been passed down to his successors, the Popes. Keys, rather than, say, a fishing net, have symbolised Peter down through the ages. In this country, there are still many pubs named “The Cross Keys”, as a reminder of Peter’s role, even though the patrons of these establishments will, by and large, have no notion that, by drinking there, they are honouring St. Peter and the Pope.
Why is Peter given such authority and such prestige by Our Lord, who uses a play on words to bestow on him a new name? “You are Petros (masculine ending) and on this Petra (the Greek for a rock has a feminine ending, which Peter, as a man, could not have) I will build my Church.” It is because Peter has proclaimed the truth about Jesus: “You are the Christ, the Son of the living God”.
Cutting through all the theories and guesses about Jesus, Simon Johnson (Simon Bar-Jonah) has set out, for eternity, what Christians must believe about Jesus if they are to bear that name. Today, no less than in the time of the apostles, there are all sorts of notions, ideas, ruminations about the true nature and identity of Jesus. If anyone wishes to be called a Christian, s/he must identify with that definition given by Peter: “You are the Christ, the Son of the living God”.
How has Peter arrived at that truth, setting aside all other notions? Our Lord answers that question for us: “Flesh and blood has not revealed this to you, but my Father who is in heaven”. Peter was divinely inspired when he proclaimed this doctrine. It was not he who was speaking, but God the Father, through God the Spirit, who was speaking in him, identifying God the Son. Hence, he was given the Keys of the Kingdom, to guard the faith of the Church, and to ensure that no falsehood should be given entry.
“Hang on!” you may say, “Peter got a lot of things wrong: he even denied his Lord. And there have been some extremely naughty Popes, down the ages.”
True, but Jesus did not say that either Peter or his successors would be sinless, or that they would always get everything right, but that there would be times when God spoke through them. However bad some of the Popes have been, none of their sins, failings or errors have taken root in the doctrine of the Church: their stewardship of the Keys is precisely stewardship, not ownership.
Yes, but what about infallibility? This is hedged around with so many safeguards. It applies only when, in consultation with the whole Church, the Pope makes an ex cathedra (from the chair [of Peter]) definition of faith or morals. This is when the whole Church concurs that, as at Caesarea Philippi, Jesus’ Father in heaven has revealed a truth to Peter. Since the definition of Papal Infallibility by the First Vatican Council in 1870, this has happened only once, in 1950, when Pius XII defined the doctrine of Our Lady’s Assumption, a doctrine which had been believed since the early years of the Church. The Keys of the Kingdom are under no threat.