infallibilitas
Infallibility
Christ's guarantee that the Church cannot err when she definitively teaches a matter of faith or morals; exercised by the pope as supreme pastor and by the bishops in communion with him, especially in an ecumenical council.
inability to fail, or to err
Infallibility is not impeccability: it does not mean the pope cannot sin, or that everything he says is protected. It is a charism, a gift, by which the Church is preserved from error when she definitively proposes a doctrine of faith or morals to be held by all. The Catechism says it belongs to the pope when, as supreme pastor, he proclaims a doctrine by a definitive act; to the body of bishops when they exercise the supreme magisterium with him, above all in an ecumenical council; and it extends as far as the deposit of divine Revelation. Definitions of this kind must be adhered to with the obedience of faith.
Councils
Where the Church settled or debated this. Follow a council to read our article on it, or the decrees themselves.
- 1869–1870First Vatican Councilthe decrees
- 1962–1965Second Vatican Councilthe decrees
Sources checked 29 September 2026