Is the pope infallible in everything he says?

No. Papal infallibility is a narrow, specific charism, not a personal quality making everything the pope says error-free. It applies only when he solemnly defines a doctrine on faith or morals as the supreme pastor, binding the whole Church, ex cathedra. His private opinions, off-the-cuff remarks, homilies, interviews, and disciplinary or political judgments are not covered and can be mistaken (CCC 891).

What Infallibility Actually Means

The First Vatican Council (1870) defined that the pope speaks infallibly only under precise conditions: when, as supreme pastor and teacher of all Christians, in virtue of his supreme apostolic authority, he defines a doctrine concerning faith or morals to be held by the whole Church. This is a rare and solemn exercise, sometimes called speaking ex cathedra, meaning "from the chair" of Peter's teaching office. Outside these conditions, the pope's statements do not carry this guarantee.

This charism is a gift given to the Church for her protection, rooted in Christ's promise to Peter and the apostles, not a personal endowment of the man who happens to hold the office. Christ prayed specifically for Peter's faith not to fail, so that he could strengthen his brethren (Luke 22:31-32), and gave Peter the keys of the kingdom with binding and loosing authority (Matthew 16:18-19).

The Ordinary Words and Acts of a Pope

A pope remains a human being capable of sin, error in judgment, poor prudential decisions, and even mistaken personal theological opinions expressed outside his official teaching office. History records popes who made political misjudgments or held disputable private views. None of this touches infallibility, because infallibility does not mean impeccability, nor does it mean omniscience, nor does it cover every homily, interview, letter, or tweet.

The Catechism situates this gift within the broader reality that the whole College of Bishops, together with the pope, also shares in this charism when they solemnly teach a matter of faith or morals as definitively to be held (CCC 891). The infallibility of the Church herself, and by extension the pope as her head, is likewise treated in CCC 889-892, which stresses that this is Christ's gift to preserve the People of God from error in matters necessary for salvation, not a suspension of the pope's human limitations.

Catholic teaching also recognizes an ordinary, non-infallible magisterium exercised through encyclicals, addresses, and routine instruction. The faithful owe this a religious submission of intellect and will, but such teaching is not irreformable in the same sense as a solemn definition, and it can in principle be developed, clarified, or even corrected over time (CCC 892). Only definitive dogmatic pronouncements on faith or morals, made under the strict conditions of Vatican I, or teachings the pope solemnly proclaims in union with the bishops as belonging to the deposit of faith, carry the guarantee of infallibility.