Papal Infallibility was defined by the First Vatican Council of 1870 as the dogma that the Pope, when he solemnly defines a matter of faith and morals ex cathedra (that is, officially), does not have the possibility of error.
Vatican Council, Sess. IV, Const. de Ecclesiâ Christi, c. iv, holds:
- We teach and define that it is a dogma Divinely revealed that the Roman pontiff when he speaks ex cathedra, that is when in discharge of the office of pastor and doctor of all Christians, by virtue of his supreme Apostolic authority, he defines a doctrine regarding faith or morals to be held by the universal Church, by the Divine assistance promised to him in Blessed Peter, is possessed of that infallibility with which the Divine Redeemer willed that his Church should be endowed in defining doctrine regarding faith or morals, and that therefore such definitions of the Roman pontiff are of themselves and not from the consent of the Church irreformable.
The only statements of the Pope that are infallible are statements that either reiterate what has always been taught by the Church or are ex cathedra solemn definitions (which can never contradict what has formerly been taught). Infallible statements in the former category are said to exercise the "Universal Magisterium"; infallible statements in the latter category are said to exercise the "Extraordinary" or "Solemn" Magisterium. Statements that exercise neither the Universal Magisterium or the Extraordinary Magisterium (i.e., statements that do not simply reiterate what has always been taught or which are not solemn definitions expressed ex cathedra) are not infallible, and are said to be an exercise of the merely authentic Magisterium. Such teaching is to be obeyed and given religious assent as long as it does not contradict infallible Magisterium and does not harm the faith or lead to sin.
The conditions required for ex cathedra teaching are mentioned in the Vatican decree:
- The pontiff must teach in his public and official capacity as spiritual head of the Church universal, not merely in his private capacity as a theologian.
- He must be teaching some doctrine of faith or morals in a manner that explicitly and solemnly defines an issue.
- His teaching cannot contradict anything the Church has taught officially and previously.
- It must be evident that he intends to teach with his supreme Apostolic authority. In other words, he must convey his wish to determine some point of doctrine in an absolutely final and irrevocable way. There are well-recognized formulas that are used to express this intention, such as "We declare, decree and define, . . .".
- It must be clear that the Pope intends to bind the whole Church. Unless the Pope formally addresses the whole Church in the recognized official way, he is assumed to not intend his teaching to be ex cathedra and infallible.
- There will be an anathema attached to the definition that outlines consequences for not assenting to it. For ex., in Pope Pius XII's infallible definition regarding the Assumption of the Virgin Mary, there is attached these words, "Hence if anyone, which God forbid, should dare willfully to deny or to call into doubt that which we have defined, let him know that he has fallen away completely from the divine and Catholic Faith."
Following the first Vatican Council, 1870, dissent, mostly among German, Austrian and Swiss Catholics, arose over the definition of Papal Infallibility. The dissenters, holding the General Councils of the Church infallible, were unwilling to accept the dogma of Papal Infallibility. Many of these Catholics formed independent communities which became known as the Old Catholic Church.
