1. The Pope is not indefectible: The Church receives the promise that it will not fail in its corporate mission – as a divinely constituted society, it must achieve the end for which Christ established it. However, this does not exclude the possibility of certain individual earthly members failing in their missions to teach, govern, and sanctify this same society; supernatural preservation from failure is not promised to any cleric – be he priest, bishop, or Pope. This is why every major heresy in history has either sprung from the ranks of the clergy or endured because of clerical weakness in combatting it. Ergo, Doctors of the Church like Aquinas and Bellarmine can teach that superiors – even Popes – must be resisted in some instances, and Catherine of Sienna can write to Pope Gregory XI: “Alas Holy Father, there are times when obedience to you leads to damnation!” We restrict papal infallibility to the papal office, not its occupant.

2. The Pope is not impeccable: One need not detail the execrable misdeeds of some of the men that have occupied the Chair of Peter in previous centuries (Crisis ran such a piece some years back) to demonstrate the point that freedom from personal sin is not conferred upon the Pope. Suffice it to recall that Saint Peter, the very Rock upon which the Church was founded, denied the Lord of Heaven in His very presence, crumpling under the interrogations of a servant girl. We restrict papal infallibility to doctrinal words, not moral deeds.

3. The Pope is not an oracle: Every word of teaching from a given Pope is not immediately divinely controlled, as though he were a perpetually prophetic Balaam, unable to speak anything but divine truth (cf. Ex 24). If this were the case, Paul need never have corrected Peter (cf. Aquinas’ treatment of Gal 2), and Pope Paul IV need not have been so concerned about the possibility of an erring successor to assert in Cum Ex Apostolatus Officio that “the Roman Pontiff… who may judge all and be judged by none in this world, may nonetheless be contradicted if he be found to have deviated from the Faith.” More to it, Pope John XXII could not have openly taught eschatological heresy two centuries prior – which, in fact, he did. There are very specific conditions for papal teachings on faith and morals to be preserved under the charism of infallibility. We restrict papal infallibility to particular doctrinal words, not all words.

4. The Pope is not inspired: Even those particular words of the Pope that are rendered infallible by the Holy Ghost are only sealed against the possibility of error. Unlike the words of Sacred Scripture, papal teachings do not have God as their Author; as such, said teachings are preserved from error and irreformable for all time, but they are not held to be the clearest or most comprehensive expressions of a given truth. This is precisely the reason for so many centuries of authentic doctrinal development; as ages run, the Spirit enables the Church to more perfectly articulate God’s Revelation in Christ (cf. Jn 16) – not by evolution or mutation (cf. Rev 22), but by refinement of expression, clarifying connections and implications, growing truth from truth in perpetual continuity, never contradiction. This is why Popes are obliged to learn the Deposit of Faith through study and other helps before making infallible definitions (cf. DZ 1836). We restrict papal infallibility to effecting freedom from error, not the fullest expression of a given truth.

It’s worth recalling that when a man becomes Pope, he remains human. Chesterton put this well in Heretics:

“When Christ at a symbolic moment was establishing His great society, He chose for its corner-stone neither the brilliant Paul nor the mystic John, but a shuffler, a snob, a coward—in a word, a man. And upon this rock He has built His Church, and the gates of Hell have not prevailed against it.”

Nor can they, despite any appearance to the contrary.

Armed with such understanding, one may avoid becoming scandalized in a period of widespread departure from Catholic doctrine and discipline even in the highest ranks of the clergy. For even if a Roman Pontiff – supreme over all earthly authorities and to whom “it is absolutely necessary for salvation that every human creature be subject“ – should (God forbid) fail to faithfully guard and expound the Deposit of Faith, yet will the Church abide, true to Christ’s promise, the indestructible and indefectible repository of Divine Revelation.

Christ has willed it so.

Now, one can then inquire: Precisely which papal teachings are guaranteed free from error, immutable and irreformable for all time? The current Code of Canon Law keeps it nice and succinct at Can 749.1, and one can try the links below for a few more authoritative treatments. Fr. Ripperger’s Magisterial Authority is also a very helpful read for further insight.

A second, related question should be raised: If Peter yet may lie, where can the faithful access the truths of Divine Revelation with certainty? Where are the authoritative sources, if not the Pope’s every word of teaching? In an age of generally deficient catechesis and widespread loss of faith, this is a pressing question.

First recommendation: attend the Traditional Latin Mass, ideally in a parish exclusively committed to offering the traditional rites. These rites are themselves a perennial theological source – “dogma in motion” – and communicate the timeless truths of the Faith in a profound and powerful way, especially as one learns the many signs and symbols (a good hand missal is indispensable – some solid options here and here – and explanatory works are helpful too, like this, this, or this). More importantly, right worship itself is the highest duty of man, which also has the happy side-effect of shaping that innate “sense of the faith” with which one can detect the tenor of truth, the voice of the Good Shepherd, in right doctrine. An insightful article on this point from Kwasniewski here.

Second recommendation: read catechisms predating Vatican II. Not because catechisms since the Council are all necessarily bad, but because there are at least enough ambiguities in them to recommend others first. Plus, if Vatican II defined no doctrine (which it didn’t), then you really shouldn’t be missing much by diving into a catechism from, say, 1880 to 1950. There’s the old Baltimore Catechism, the Penny Catechism, the Catechism of Pius X, the works of Hay or Spirago – and for a deeper dive into dogmatic theology, there’s the redoubtable Ott and the sources à la Denzinger.

Third recommendation, especially now in Lent: Pray – especially with Scripture (it’s infallible and inspired) and the Rosary – and fast. Our Pope and all our shepherds have great need of our prayers.

And bravo the restoration!