Papal infallibility

Pope Pius IX (1846–1878), during whose pontificate the doctrine of papal infallibility was dogmatically defined by the First Vatican Council.

Papal infallibility is a dogma of theCatholic Church that states that, in virtue of the promise of Jesus to Peter, the Pope is preserved from the possibility of error "when, in the exercise of his office as shepherd 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."[1][2]

This doctrine was defined dogmatically at the First Ecumenical Council of the Vatican of 1869–1870, but had been defended before that, existing already in medieval theology and being the majority opinion at the time of theCounter-Reformation.[3]

According to Catholic theology, there are several concepts important to the understanding of infallible, divine revelation: Sacred Scripture, Sacred Tradition, and the Sacred Magisterium. The infallible teachings of the Pope are part of the Sacred Magisterium, which also consists of ecumenical councilsand the "ordinary and universal magisterium." In Catholic theology, papal infallibility is one of the channels of the infallibility of the Church. The infallible teachings of the Pope must be based on, or at least not contradict, Sacred Tradition or Sacred Scripture.

The doctrine of infallibility relies on one of the cornerstones of Catholic dogma: that of Petrine supremacy of the pope, and his authority as the ruling agent who decides what are accepted as formalbeliefs in the Roman Catholic Church.[4]The use of this power is referred to as speaking ex cathedra.[5] The solemn declaration of papal infallibility byVatican I took place on 18 July 1870. Since that time, the only example of anex cathedra decree took place in 1950, when Pope Pius XII defined theAssumption of Mary as an article of faith.[6] Prior to the solemn definition of 1870, there were other decrees which fit the definition of ex cathedra, for example, Pope Boniface VIII in the bullUnam Sanctam of 1302,[7][8][9] and Pope Pius IX in the Papal constitutionIneffabilis Deus of 1854.[10][  

Coined from wikipedia