One of the most widespread errors among Catholics today is the idea that the Pope, Ecumenical Councils, and the body of Bishops teaching with the Pope can err to any extent, unless they are teaching infallibly. This claim is contrary to dogma. If the Church could err to any extent, except when She teaches infallibly, then She would not be indefectible. Ecumenical Councils are not frequent. Papal Infallibility is not exercised daily or weekly. And for a teaching to be infallible under the ordinary universal Magisterium usually takes a long period of time, over which the Roman Pontiff or successive Roman Pontiffs and the body of Bishops dispersed in the world come to an agreement on one position definitively to be held by the whole Church on a matter of faith or morals. If the Church were only indefectible when exercising the infallibility of the Magisterium, then She would be able to defect most of the time. And that is not what Christ promised:

[Matthew]
{16:18} And I say to you, that you are Peter, and upon this rock I will build my Church, and the gates of Hell shall not prevail against it.
{16:19} And I will give you the keys of the kingdom of heaven. And whatever you shall bind on earth shall be bound, even in heaven. And whatever you shall release on earth shall be released, even in heaven.”

The whole Church is founded upon Peter as upon a rock, always and not only when exercising infallibility. The gates of Hell shall not prevail against the Church, never at any time and not only when exercising infallibility. The Popes, Councils, Fathers, Doctors, and Saints have always interpreted this verse as a guarantee that applies to the Church on earth at all times. Even when the Church exercises Her authority from Christ in a way that is non-infallible, She has divine help (Donum Veritatis 17) and She remains indefectible and She remains founded on the Rock that is Peter and his successors. But Peter and his successors, each of the Roman Pontiffs, would not be called a Rock by Christ the Lord if they could lead the Church astray or go astray from the true faith themselves. For then either the Church would fail, being founded on a teacher of heresy or on a heretic — which is not possible.

As for the keys of the kingdom of heaven, this authority given to Peter and his successors has never been restricted in the teachings of Popes, Councils, Fathers, Doctors, and Saints to that which is infallible (Papal Infallibility, Conciliar Infallibility, ordinary universal Magisterium, dogmatic facts). Whatever the Roman Pontiff binds or looses is bound or loosed even in Heaven. Never has this authority been understood to be restricted to what is infallible. But since the authority is confirmed by the Lord Jesus in Heaven, and is binding over the whole Church on earth, then these decisions of the Roman Pontiff on doctrine or discipline, whether infallible or non-infallible, cannot contradict the indefectibility of the Church.

Donum Veritatis: “17. Divine assistance is also given to the successors of the apostles teaching in communion with the successor of Peter, and in a particular way, to the Roman Pontiff as Pastor of the whole Church, when exercising their ordinary Magisterium, even should this not issue in an infallible definition or in a “definitive” pronouncement but in the proposal of some teaching which leads to a better understanding of Revelation in matters of faith and morals and to moral directives derived from such teaching.

“One must therefore take into account the proper character of every exercise of the Magisterium, considering the extent to which its authority is engaged. It is also to be borne in mind that all acts of the Magisterium derive from the same source, that is, from Christ who desires that His People walk in the entire truth. For this same reason, magisterial decisions in matters of discipline, even if they are not guaranteed by the charism of infallibility, are not without divine assistance and call for the adherence of the faithful.”

Notice that infallible teachings can be either definitions or definitive pronouncements. Infallibility is not restricted to definitions. But the main point in the quote above is that, apart from what is infallible, the Church still has divine assistance, in both doctrine and discipline, in what is non-infallible.

Indefectibility is not equivalent to infallibility. The indefectibility extends to Her infallible teachings as well as Her non-infallible teachings, to Her infallible decisions of discipline (dogmatic facts) as well as to Her non-infallible decisions of discipline. And this necessarily implies that the Roman Pontiff, the body of Bishops led by him, and Ecumenical Councils approved by the Roman Pontiff can never teach heresy or lead the Church or the faithful astray.

Therefore, indefectibility protects the Roman Pontiff in his exercise of the Keys of Saint Peter from every grave error on doctrine and discipline, and the same is true for an Ecumenical Council approved by the Pope and for the body of Bishops in agreement with the Pope, including both infallible and non-infallible decisions of doctrine and discipline.

The claims of the restorationists that multiple Popes have taught heresy, have led the Church astray, have committed apostasy, idolatry, or heresy, and that one or more Ecumenical Councils have similarly erred is contrary to the dogmas of the indefectibility of the Church, and the charism of truth and never-failing faith of the Roman Pontiff, as well as contrary to the clear teaching and promise of Christ (Mt 16:18; Lk 22:32).

by
Ronald L. Conte Jr.
Roman Catholic theologian and translator of the Catholic Public Domain Version of the Bible.

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