Why Do Catholics Have a Pope, and What Does He Actually Do?

The Most Famous Bishop in the World

When a new Pope is elected, the whole world watches the white smoke rise from the Sistine Chapel. Even people with no interest in religion know who the Pope is. Yet many Catholics, let alone non-Catholics, are unsure why the Church has a Pope at all, or what he actually does all day.

The Church’s answer is simple: Catholics have a Pope because Christ gave His Church one (CCC 880–882).

It Begins With Peter

The papacy begins in the Gospels, with St Peter.

Jesus gave Simon a new name: Kepha in Aramaic, Petros in Greek, meaning “rock.” Then He said: “You are Peter, and upon this rock I will build My Church, and the gates of hell shall not prevail against it. And I will give to you the keys of the kingdom of heaven” (Matthew 16:18–19).

The keys were a well-known image. In the Old Testament kingdom, the king’s chief steward held the keys of the house and governed in the king’s name (Isaiah 22:22). By giving Peter the keys, Jesus made him the chief steward of His Church.

Jesus gave Peter a special role in other places too. At the Last Supper He prayed for Peter’s faith and told him to “strengthen your brethren” (Luke 22:32). After the Resurrection, He told Peter three times, “Feed My sheep” (John 21:15–17). In the Acts of the Apostles, Peter leads the early Church: he preaches the first sermon at Pentecost, receives the first Gentile converts, and speaks decisively at the Council of Jerusalem.

From Peter to the Pope

Peter went to Rome, led the Church there, and was martyred there under the Emperor Nero in the 60s. His tomb lies beneath St Peter’s Basilica.

Christ intended His Church to last until the end of time, so the role He gave Peter was meant to continue. The Bishop of Rome is Peter’s successor, just as the other bishops are successors of the apostles (CCC 880–882). The early Christians recognised this. By the end of the first century, the Church of Rome was already intervening to settle disputes in other churches, and writers like St Irenaeus, around 180, listed the bishops of Rome in order back to Peter as a guarantee of true teaching.

The word Pope simply comes from the Greek pappas, meaning “father.”

What the Pope Actually Does

The Pope has several roles at once.

He is the Bishop of Rome. Before anything else, he is the bishop of a particular diocese, with its own parishes and people. His cathedral is not St Peter’s but the Basilica of St John Lateran.

He is the visible source of the Church’s unity. The Catechism calls him the “perpetual and visible source and foundation of the unity” of the bishops and of the whole Church (CCC 882). Being in communion with the Pope is what holds more than a billion Catholics together as one Church.

He teaches the Faith. Through encyclicals, apostolic exhortations, homilies and audiences, the Pope teaches and explains the faith for the whole Church, applying it to new questions as they arise.

He governs the Church. The Pope has full, supreme and universal authority over the Church (CCC 882). In practice this means appointing bishops, approving religious orders for the whole Church, setting universal laws, and overseeing the Church’s central offices, known as the Roman Curia.

He declares saints. It is the Pope who canonises saints, solemnly declaring that a person is in heaven and may be honoured by the whole Church.

He works with the bishops. The Pope does not rule alone. Together with all the bishops of the world, he forms the College of Bishops, which shares responsibility for the whole Church (CCC 883). But the College has no authority apart from him.

What Is Papal Infallibility?

This is probably the most misunderstood teaching about the Pope.

Papal infallibility does not mean that the Pope is sinless. Popes go to Confession like everyone else, and some have been notorious sinners. Nor does it mean that every word he says is free from error. His opinions in interviews, his personal theological views, and his decisions about Church governance are not infallible.

Infallibility means that when the Pope, as supreme teacher of the Church, solemnly defines a doctrine of faith or morals to be held by the whole Church, the Holy Spirit preserves him from error (CCC 891). This is called speaking ex cathedra, Latin for “from the chair,” meaning from Peter’s chair of teaching.

This happens very rarely. The two clearest modern examples are the definition of the Immaculate Conception in 1854 and the Assumption of Mary in 1950.

Infallibility is not a power to invent new doctrines. It is a guarantee that the Pope will not lead the Church into error when he solemnly hands on the faith received from the apostles. It was formally defined by the First Vatican Council in 1870, but the belief behind it is far older.

What About Bad Popes?

There have been bad popes. The Church does not hide this. Some were worldly, some were weak, and a few were genuinely scandalous.

Yet none of them ever solemnly taught error to the whole Church. Catholics see this as remarkable evidence that Christ’s promise to Peter has been kept. The gates of hell have not prevailed, even when the man on Peter’s chair has been a poor one.

Why It Matters

Without a visible head, Christians have no final way to settle disputes about what Christ taught. The history of Christianity since the Reformation shows how quickly division multiplies without one.

The Pope is a gift Christ gave His Church to keep her united in truth. That is why Catholics pray for him at every Mass, by name, and why loyalty to the Pope has always been a sign of being Catholic.

See also What Are the Four Marks of the Church? and Do Catholics Have to Believe Everything the Church Teaches?

Go deeper: What Is Apostolic Succession and Why Does It Matter?