The installation of a new pope always brings to mind things both ancient and new. There is much that is refreshingly “new” about Pope Francis. He is the first pope from the New World; the first from outside Europe since the 8th century (when there was a Syrian); the first Jesuit; the first to assume the name of the man from Assisi.

We Catholics, and even non-Catholics, can’t help admiring a prince of the church who cooks his own meals, rides the buses, and lives in a small apartment rather than the episcopal palace.

Francis’ career in the church, which began at the relatively late age of 32, has been at the service of the poor and marginalized. This is a reminder that Christian faith should always involve an unassuming ministry to those least able to help themselves.

But with all the focus on the life and personality of Pope Francis, there can be a tendency to overlook what we Catholics most revere about the papacy. We are happy to welcome as pope a Polish “rock star,” or a quiet German scholar, or a “man of the people” from Buenos Aires. But in the end it is the Chair of Peter, and not the personality of the man who sits on it, that has held the Catholic Church together for two millennia.

Even the most stringently secular viewpoint has to recognize that there is no institution like the papacy. Thomas Babington Macaulay, the Victorian essayist, and no friend of Catholicism, wrote that the papacy “joins together the two great ages of human civilization. No other institution is left standing which carries the mind back to the times when the smoke of sacrifice rose from the Pantheon. ... The proudest royal houses are but of yesterday, when compared with the line of the supreme pontiffs .”

Despite manifest defects over the centuries, the papacy has made deep and lasting contributions to humanity. Popes chartered some of the earliest western universities, preserved the patrimony of Greece and Rome, opened the first public art museums, and gave us the Gregorian calendar that we all use today.

Popes have also been great spotters of talent. The medieval pontiff Innocent III was approached one day by an unknown man in poor dress who kept company with lepers and mendicants. Innocent approved of what this holy ragamuffin was trying to do, thereby encouraging an awakening in the mind of Europe. Saint Francis has been called the “morning star” of the Renaissance; but his influence would have been limited without the backing of the papacy.

Yet such benefits are not the primary reason for a Catholic’s veneration of the papacy. We venerate the office because it was founded by Jesus Christ himself. He called Peter the “rock” on which he was going to build his church, adding, “And I will give you the keys of the kingdom of heaven; and whatever you shall bind on earth shall be bound in heaven, and whatever you shall loose on earth shall be loosed in heaven.”

The interesting thing is that Christ chose a man who was scandalously unloyal. Peter denied Christ three times and then went into hiding during the crucifixion. Christ explicitly warned that there would be scandals in the church, and they started with the man who would become the first bishop of Rome.

Christ did not promise that Peter and his successors would all be saints. Some, in fact, have been scoundrels. What he did promise was that the faith handed on to the Apostles would be preserved in the church, and ultimately through the successors of Peter, the popes.

Early Christians recognized this authority. Saint Irenaeus, wrote around the year 180 that if anyone wished to know true Christian doctrine, he had only to find those churches with a line of bishops going back to one of the Apostles.

But, he writes, it is simpler, and suffices, to find out the teaching of the Roman See: “For with this church all other churches must bring themselves into line, on account of its superior authority.”

Papal authority is not authoritarianism. It is simply there as a sure guidepost. The 19th century convert John Henry Newman pointed out that a divine revelation is not given if there is no authority to decide what has been given. Over the millennia, this has been the job of the bishops in union with the pope, who has the final say. This authority produced the canon of the New Testament, whose twenty-seven books were not definitively collected until the fourth century.

The doctrine of papal infallibility is far more limited than widely supposed. It says that when the successor of Peter makes a solemn declaration about faith and morals, he is guarded by the Holy Spirit against teaching error. Far from giving the pope an arbitrary authority to impose his views, infallibility prevents him from rashly undoing what has been handed down from the Apostles.

But the pope is not just a teacher. Christ said to Peter, “Strengthen your brethren.” He was referring to the other disciples, who certainly needed it, but perhaps to all Christians. The word “pope” comes from the Italian for “papa.” Last week week we saw a man in white standing at the Vatican loggia, suddenly taking on enormous burdens, but who smiled at each of us, Catholic or not, as a father.

Monsignor Thomas Bohlin is the U.S. Vicar of Opus Dei.