Editor’s note: this and related articles have now been published in a book entitled: Disputed Questions on Papal Infallibility (Os Justi Press, 2022).
Whether the Pope Speaks Infallibly
in Ordinatio Sacerdotalis?
Objection 1. It seems that the pope does not speak infallibly in Ordinatio Sacerdotalis (1994). For according to Cardinal Ratzinger: “In this case, an act of the ordinary papal magisterium, in itself not infallible, witnesses to the infallibility of the teaching of a doctrine already possessed by the Church.” Hence, as Sullivan says: “This language comes very close to that of a solemn definition, but we are assured by Cardinal Ratzinger that it was not the intention of John Paul II to speak ex cathedra.”
Objection 2. Furthermore, according to Archbishop Bertone: “It seems a pseudo-problem to wonder whether this papal act of ‘confirming’ a teaching of the ordinary, universal magisterium is infallible or not.” For even though it is not infallible of itself, it participates in the infallibility of the ordinary and universal magisterium, “which includes the pope not as a mere bishop but as the head of the episcopal college.”
On the contrary, according to Pope Benedict XVI: “Blessed Pope John Paul II stated irrevocably that the Church has received no authority for this from the Lord.” And again: “The late Pope John Paul II has decided infallibly and irrevocably that the Church has not the right to ordain women to the priesthood.”
I answer that, it must be said that the pope speaks infallibly in Ordinatio Sacerdotalis, when he says: “Wherefore, in order that all doubt may be removed regarding a matter of great importance, a matter which pertains to the Church’s divine constitution itself, in virtue of Our ministry of confirming the brethren (cf. Lk 22:32), We declare that the Church has no authority whatsoever to confer priestly ordination on women and that this judgment is to be definitively held by all the Church’s faithful.”
There are, as has been shown, three necessary conditions for an infallible papal definition. In the case of Ordinatio Sacerdotalis there can be no doubt that the first condition (on the part of the subject) is fulfilled. For Pope John Paul II explicitly addresses this apostolic letter to all the bishops of the Catholic Church and invokes his “ministry of confirming the brethren (cf. Lk 22:32),” thereby recalling the words of the Second Vatican Council, which cites the same passage of Luke’s Gospel where it says that the pope is infallible when: “as the supreme shepherd and teacher of all the faithful, who confirms his brethren in their faith (cf. Lk 22:32)…”
With regard to the second condition (on the part of the object), the matter in question is explicitly presented as “a matter which pertains to the Church’s divine constitution itself,” which is necessarily a matter pertaining to faith. Confirmation of this appears in the affirmative response of the CDF to the question: “Is the teaching that the Church has no authority whatsoever to confer priestly ordination on women, which is presented in the apostolic letter Ordinatio Sacerdotalis to be held definitively, to be understood as pertaining to the deposit of faith?” For a doctrine which pertains to the deposit of faith is one which is either revealed or necessarily connected to divine revelation. In either case, it falls within the scope of papal infallibility.
With regard to the third condition (on the part of the act itself), there has been some confusion over the formula employed by the pope in proposing the doctrine as “to be definitively held,” since this same formula is used by the Second Vatican Council to describe the mode of infallible teaching of the ordinary and universal magisterium, whereas the mode of infallible teaching proper to the pope is described in the same place as proclaiming a doctrine “by a definitive act.” This has led some theologians to wonder whether the pope was exercising (or attempting to exercise) the infallibility of the ordinary and universal magisterium. But such speculation is not to the point. For, as Ansgar Santogrossi shows, the declaration of Ordinatio Sacerdotalis is a proper exercise of papal infallibility in its own right, as can be proved in two ways.
First, from the words of Gasser’s relatio on papal infallibility, for the very property and note of a definition in the proper sense is “the manifest intention of defining doctrine, either of putting an end to doubt (fluctuationi finem imponendi) about a certain doctrine or of defining a thing by giving a definitive judgment (definitivam sententiam) and proposing that doctrine as one which must be held (tenendam) by the universal Church.” And this intention is manifest in Ordinatio Sacerdotalis. For Pope John Paul II expressly intends to remove all doubt, saying: “Wherefore, in order that all doubt may be removed.” And he does so by proposing his judgment (sententia) as “definitively to be held (definitive tenendam) by all the Church’s faithful.”
Second, it is indisputable that the bishops dispersed throughout the world would teach infallibly if they proposed the very same doctrine in the very same manner—namely, as a judgment to be definitively held by all the faithful. For according to the Second Vatican Council, the bishops “dispersed through the world, but still maintaining the bond of communion among themselves and with the successor of Peter,” are infallible when “authentically teaching matters of faith and morals, they are in agreement on one position (sententiam) as definitively to be held (definitive tenendam).” But if one were to deny that the pope also speaks infallibly when he, as head of the Church, proposes his judgment (sententia) in a matter of faith or morals as definitively to be held (definitive tenendam), then one would fall into the error of the Gallicans, according to which the bishops have a greater teaching authority than the pope, contrary to the solemnly defined teaching of Vatican I that the pope possesses the fullness of the supreme power of jurisdiction over the universal Church, which includes the power of the magisterium. Hence, it must be admitted that pope speaks infallibly in Ordinatio Sacerdotalis.
Reply to Objection 1. To the first it must be said that the private opinion of Cardinal Ratzinger is not decisive. Nor is the question of whether or not Pope John Paul II consciously understood himself to be speaking ex cathedra. The decisive question is only whether he intended to speak definitively, that is, conclusively, on a matter of faith or morals, for the whole Church. And this must be judged in light of the intention expressed in the text itself, and not by the private opinions of the pope’s friends or advisors, no matter how well informed they may be of his private thoughts and intentions. Moreover, Ratzinger’s assertion appears to be based on the assumption that the pope can speak infallibly only when he defines a new dogma (or doctrine), which is false, as shown above (Question I, article 4).
Reply to Objection 2. To the second it must be said that it is not a pseudo-problem, but an important question, to ask whether the act by which a pope confirms a teaching of the ordinary and universal magisterium is infallible or not. For in the absence of a solemn definition, doubt may arise as to whether a doctrine has in fact been definitively taught by the ordinary and universal magisterium, and this indeed has happened with regard to the question of women’s ordination. In such a case, an infallible act of confirmation would remove all grounds for doubt about the truth of the doctrine. But if the act of confirmation were not infallible of itself, then the definitive status of the doctrine would still rest on the teaching of the ordinary and universal magisterium, which was precisely the point under dispute, and so the doubts of many would not be effectively resolved.
Whether the Pope Speaks Infallibly
in Veritatis Splendor?
Objection 1. It seems that the pope does not speak infallibly in Veritatis Splendor (1993). For according to Archbishop Bertone: “In the Encyclicals Veritatis splendor and Evangelium vitae and in the Apostolic Letter Ordinatio sacerdotalis, the Roman pontiff intended, though not in a solemn way, to confirm and reaffirm doctrines which belong to the ordinary, universal teaching of the magisterium, and which therefore are to be held in a definitive and irrevocable way.” And again: “These documents deal with teachings not proposed or confirmed by the magisterium in the form of a definition (solemn judgement).”  But if the teaching of Veritatis Splendor is not proposed in a solemn way, in the form of a definition or solemn judgment, then it is not proposed infallibly, as shown above.
Objection 2. Furthermore, if Veritatis Splendor contained ex cathedra teaching, there would be at least some reputable Catholic theologians maintaining this thesis; but there seem to be none.
On the contrary, Bertone errs in denying the infallibility of Evangelium Vitae and Ordinatio Sacerdotalis, as shown above. Therefore, it is likely that he also errs in denying the infallibility of Veritatis Splendor, since, according to his own words, Pope John Paul II intended, in each of these three cases, “to confirm and reaffirm doctrines which belong to the ordinary, universal teaching of the magisterium, and which therefore are to be held in a definitive and irrevocable way.”
I answer that, it must be said that Pope John Paul II speaks infallibly on the central doctrine of this encyclical letter, which is “the reaffirmation of the universality and immutability of the moral commandments, particularly those which prohibit always and without exception intrinsically evil acts.” This can be seen from an examination of the three essential conditions for papal infallibility.
First, on the part of the subject, the pope explicitly appeals to his ministry of confirming his brethren (cf. Lk 22:32) and invokes his apostolic authority, saying: “Each of us knows how important is the teaching which represents the central theme of this encyclical and which is today being restated with the authority of the Successor of Peter.”
Second, on the part of the object, John Paul II presents this central teaching as a moral doctrine intimately connected to divine revelation, saying: “In teaching the existence of intrinsically evil acts, the Church accepts the teaching of Sacred Scripture. The Apostle Paul emphatically states: ‘Do not be deceived: neither the immoral, nor idolaters, nor adulterers, nor sexual perverts, nor thieves, nor the greedy, nor drunkards, nor revilers, nor robbers will inherit the Kingdom of God’ (1 Cor 6:9–10).”
Third, on the part of the act, the reaffirmation of the existence of intrinsically evil acts is expressed in the encyclical letter as follows:
One must therefore reject the thesis, characteristic of teleological and proportionalist theories, which holds that it is impossible to qualify as morally evil according to its species—its ‘object’—the deliberate choice of certain kinds of behavior or specific acts, apart from a consideration of the intention for which the choice is made or the totality of the foreseeable consequences of that act for all persons concerned.
For this reason—we repeat—the opinion must be rejected as erroneous which maintains that it is impossible to qualify as morally evil according to its species the deliberate choice of certain kinds of behavior or specific acts, without taking into account the intention for which the choice was made or the totality of the foreseeable consequences of that act for all persons concerned.
By these words the pope not only reaffirms the existence of intrinsically evil acts, but proclaims this doctrine by a definitive act. In the first place, the pope repeats his central condemnation twice in the space of four paragraphs, which is highly unusual and cannot but give added force to the condemnation, for the frequent repetition of a doctrine is one of the notes by which the degree of authority of papal statements is to be judged, as the Second Vatican Council teaches. Secondly, the pope qualifies the condemned opinion as “erroneous” (ut erronea), which, in the traditional terminology of theological censures, is the negative equivalent of a theologically certain truth of Catholic doctrine, just as ‘heretical’ is the negative equivalent of a dogma to be believed by divine and Catholic faith. Finally, the pope declares that this erroneous proposition “must be rejected” (respuenda est), thus expressing the obligatory nature of the condemnation. For to say that a proposition “must be rejected as erroneous” is equivalent to saying that the opposing truth “must be held as true,” which is the same as proposing that truth as one that is definitively to be held. And this is the essential note of definition, as shown above (question 1 article 1).
Reply to Objection 1. To the first it must be said that Bertone’s opinion appears to be based on the assumption that the pope can speak infallibly only when he defines a new dogma (or doctrine), which is false, as shown above (question 1 article 4).
Reply to Objection 2. To the second it must be said that this objection would have more weight were it not for the fact that this encyclical was published at a time when most Catholic theologians routinely denied the infallibility of all but the most solemn dogmatic definitions. In such a context it is unsurprising that very little consideration has been given to the question of infallible teaching in Veritatis Splendor.
Whether the Credo of Paul VI
is an Infallible Profession of Faith?
Objection 1. It seems that the creed of Paul VI (1968) is an infallible profession of faith. For it was issued by Pope Paul VI, in fulfillment of “the mandate entrusted by Christ to Peter . . . to confirm our brothers in the faith.” And the profession of faith is a pre-eminent form of infallible definition. For as St. Thomas says: “To publish a new edition of the symbol belongs to that authority which is empowered to decide matters of faith finally (sententialiter determinare), so that they may be held by all with unshaken faith. Now this belongs to the authority of the Sovereign Pontiff.”
Objection 2. Furthermore, Pope Paul VI introduces his profession of faith, saying: “Today We are offered the opportunity of declaring Our judgment (sententia) in a more solemn mode (sollemniore modo).” But the solemn judgments of the pope are infallible.
On the contrary, the pope himself says in the preamble to this creed that it is “not, strictly speaking, a dogmatic definition.”
I answer that, it must be said that the creed of Paul VI would certainly qualify as an infallible profession of faith were it not for the substantial element of doubt introduced by his own qualification when he says, in the introductory part of the text itself, that this creed is “not, strictly speaking, a dogmatic definition.” It may be objected that by these words the pope denies only that this creed is dogmatic and not that it is definitive, thus leaving open the possibility that it is an infallible definition of doctrine (de fide tenenda). But against this is the consistent use of the term ‘credimus’ (‘we believe’), which is the language of properly dogmatic professions of faith, rather than tenemus (‘we hold’), which would indicate a merely doctrinal definition. Moreover, the contents of the creed, which “repeats in substance . . . the creed of Nicaea,” is evidently dogmatic and not merely doctrinal.
Hence it seems more probable that these words manifest a deliberate intention on the part of Paul VI to downgrade the authority of his profession of faith out of a fear that, if he “were to have the air of prescribing or imposing his profession of faith in the name of his Magisterium, either he would have to tell the whole truth, raising a storm, or would have to take precautions, avoiding dealing with the more dangerously threatened points, and that would be the worst thing of all.” This casts substantial doubt on the infallibility of Paul VI’s profession of faith; and according to the Code of Canon Law: “No doctrine is understood to be defined infallibly unless this is manifestly evident.”
From this the replies to the objections should be clear.
Whether the Pope Speaks Infallibly
in Humanae Vitae?
Objection 1. It seems that the pope does not speak infallibly in Humanae Vitae (1968). For the infallibility of the Church does not extend beyond matters of faith and morals that are directly contained in divine revelation or that are required for safeguarding and expounding the same. But the prohibition of artificial birth control is a specific moral norm of natural law that does not appear to be directly revealed, nor is it strictly necessary for safeguarding and expounding divine revelation. Therefore, this doctrine cannot be taught infallibly.
Objection 2. Furthermore, according to the remarks of Ferdinando Lambruschini in his presentation of the encyclical at the Vatican press conference, its teaching is not infallible.
Objection 3. Furthermore, none of the customary phrases by which the popes have traditionally signaled their intention to define a doctrine are present in Humanae Vitae.
Objection 4. Furthermore, according to the Code of Canon Law: “No doctrine is understood to be defined infallibly unless this is manifestly evident.” Now if it were manifestly evident that the pope was speaking infallibly in Humanae Vitae, then this would be recognized by a consensus of Catholic theologians. But in fact most Catholic theologians do not regard the teaching of Humanae Vitae as infallible.
On the contrary, according to Ermenegildo Lio, in his book Humanae Vitae e Infallibilità, for which he received a personal letter of thanks from Pope John Paul II, Humanae Vitae contains a solemn ex cathedra definition of the intrinsic immorality of artificial birth control.
I answer that, it must be said that the condemnation of artificial methods of birth control in Humanae Vitae fulfills the three essential criteria set forth by Vatican I for the exercise of papal infallibility. In the first place, there can be no doubt that the pope is exercising his office of pastor and teacher of all Christians. For the encyclical is addressed “to his venerable brothers the patriarchs, archbishops, bishops and other local ordinaries in peace and communion with the Apostolic See, to the clergy and faithful of the whole Catholic world, and to all men of good will.” Moreover, the pope explicitly declares that he speaks “in virtue of the mandate entrusted to us by Christ.”
Second, as regards the object of papal infallibility, the teaching of the encyclical is presented as “a teaching which is based on the natural law as illuminated and enriched by divine revelation.” Here there is some question as to whether this moral doctrine is contained at least within the secondary object of infallibility. That it is can be proved in two ways.
In one way, the argument proceeds from the positive assertion that the authority of the Church’s magisterium extends to the whole natural law, as Paul VI says: “No member of the faithful could possibly deny that the Church is competent in her magisterium to interpret the natural moral law.” But the infallibility of Church extends as far as her magisterium itself extends. For the object of the authentic magisterium in general, and of the infallible magisterium in particular, are described in precisely the same way as “matters of faith and morals.” For the Second Vatican Council says: “In matters of faith and morals, the bishops speak in the name of Christ and the faithful are to accept their teaching and adhere to it with a religious assent,” and this pertains to the authentic magisterium. In the same place, the object of the infallible teaching of the ordinary and universal magisterium is described as “matters of faith and morals.” And again, the object of infallible papal teaching is also said to be “doctrine of faith or morals.” These identical descriptions are due to the fact that the infallible magisterium and the merely authentic (non-definitive) magisterium are not distinguished by their object, but by their mode of teaching. For the former is proclaimed “by a definitive act,” whereas in the latter case, the pope or the college of bishops “do not intend to proclaim these teachings by a definitive act.”
In another way, the argument proceeds from the close connection of the natural law to the ultimate purpose of divine revelation. For the secondary object of the Church’s infallibility extends to every truth that is “intimately connected” to divine revelation, whether more or less strictly, as Gasser says: “Together with revealed truths, there are other truths more or less strictly connected. These truths, although they are not revealed in themselves, are nevertheless required in order to guard fully, explain properly, and define efficaciously the very deposit of faith.” Now the truth concerning particular moral norms of the natural law is necessarily connected with divine revelation on account of the ultimate purpose of divine revelation, which is man’s salvation. For as Paul VI says: “The natural law, too, declares the will of God, and its faithful observance is necessary for men’s eternal salvation.” And again, according to Pope Pius XI: “Every human action has a necessary connection with man’s last end, and therefore cannot be withdrawn from the dictates of the divine law, of which the Church is guardian, interpreter and infallible mistress.” The infallibility of the Church, therefore, extends to the whole range of human actions, insofar as they are intrinsically good or evil, whether on account of the law revealed by God or on account of the law written by God upon the human heart.
The third essential condition for the exercise of papal infallibility is the note of definition, which appears when the pope “directly and conclusively pronounces his judgment” (suam sententiam directe et terminative proferat) concerning faith or morals. Now in the condemnation of artificial methods of birth control at the heart of Humanae Vitae, the pope directly and conclusively pronounces his sentence with the manifest intention of putting an end to doubt about this question. For the pope declares that withdrawal, abortion, sterilization, and contraception must be rejected (respuendum est) and condemned (damnandum est) absolutely (omnino), thus manifestly intending to oblige the faithful to give a firm and unqualified assent to the doctrine of the intrinsic immorality of these acts.
For he says first:
Therefore, relying on these first principles of a human and Christian doctrine of marriage, We must once more declare that the direct interruption of the generative process already begun and, above all, all direct abortion, even for therapeutic reasons, are to be absolutely rejected (omnino respuendam esse) as lawful means of regulating the number of children.
Then he adds:
Equally to be condemned (Pariter damnandum est), as the magisterium of the Church has many times taught, is direct sterilization, whether of the man or of the woman, whether permanent or temporary.
And then again:
Similarly to be rejected (Item respuendus est) is any action before, during, or after sexual intercourse, that is specifically intended to prevent procreation, whether as an end or as a means.
Therefore, since it is the same thing to say that these acts must be absolutely rejected and condemned as unlawful and to say that their intrinsic immorality must be definitively held, it must be concluded that these condemnations manifest the essential note of definition, and hence that Humanae Vitae contains infallible papal teaching.
Reply to Objection 1. To the first it must be said that specific moral norms of the natural law fall at least within the secondary object of infallibility on account of their necessity for salvation, which is the ultimate purpose of divine revelation, as said above. Moreover, this objection would undermine the whole doctrine of papal infallibility. For if it were admissible for anyone to judge that the pope does not speak infallibly in a certain instance because the doctrine proposed does not, according to his own opinion, pertain to the deposit of faith, then it would be possible to assert that any papal definition, such as even that of the Immaculate Conception or the Assumption of Mary, is not infallible because, according to his own opinion, the doctrine in question is neither contained in divine revelation nor is it required for the safeguarding and exposition of the deposit of the same. But this is absurd. Rather, as Jean-Marie Hervé notes:
It is also up to the Church to decide how far her infallibility extends: otherwise there could never be any certainty as to whether, in defining something, she had transgressed the limits of her magisterium. In that case infallibility would be placed in grave peril, and the whole of religion would turn out to be placed in doubt. From this it follows that, if the Church declares that something pertains to her magisterium, or proposes it as requiring the assent of faith, such a decree is to be held as infallible.
What is necessary to determine with regard to the object of papal infallibility, therefore, is not whether the doctrine taught is in fact a matter of faith or morals, but whether it is being proposed as such.
Reply to Objection 2. To the second it must be said that this represents no more than the personal opinion of Lambruschini. Moreover, this aspect of his remarks was erased from the official account of the press conference, which appeared the next day in L’Osservatore Romano.
Reply to Objection 3. To the third it must be said that the popes who have reigned over the Church since the Second Vatican Council, which inaugurated an era of heightened emphasis on collegiality and ecumenism, have tended to avoid the more solemn sounding formulae in their teaching. Such solemn formulae, however, although generally sufficient to indicate infallible teaching, are not strictly necessary (as shown above, question 1 article 7).
Reply to Objection 4. To the fourth it must be said that, although the consensus of Catholic theologians may be sufficient, it is not necessary for manifesting the fact of an infallible definition. As Brian Harrison notes: “Such an interpretation of the code would in effect give the theological ‘establishment’ at any given period a kind of veto power over the Roman pontiff himself,” which is absurd. On the contrary, “it is ‘manifestly the case’ that a certain doctrine is infallibly defined whenever it emerges plainly and clearly from the words of the relevant documents that there was an intention of giving a certain, final, decisive judgment on a point of faith or morals to be held by the universal Church.”
 Ratzinger, “Letter Concerning the CDF Reply.”
 Sullivan, Creative Fidelity, 22.
 Bertone, “Magisterial Documents and Public Dissent.”
 Pope Benedict XVI, Homily for Chrism Mass, April 5, 2012.
 Letter of Pope Benedict XVI to Bishop William Morris, cited by Morris in Benedict, Me and the Cardinals Three: The Story of the Dismissal of Bishop Bill Morris by Pope Benedict XVI (Adelaide: ATF Press, 2014), 179.
 Pope John Paul II, Apostolic Letter Ordinatio Sacerdotalis (1994), §4. Note: the official Latin text uses the traditional papal plural, yet the English and Italian text contained on the Vatican website translates “Nostri” and “declaramus” incorrectly as singular.
 Vatican II, Lumen Gentium, §25.
 CDF, Response to Dubium Concerning Ordinatio Sacerdotalis (1995).
 Vatican II, Lumen Gentium, §25.
 Ansgar Santogrossi, “Ordinatio Sacerdotalis: A definition ex cathedra,” Homiletic and Pastoral Review (Feb. 1999): 7–14.
 Mansi, 52:1225 C.
 John Paul II, Ordinatio Sacerdotalis, §4.
 Vatican II, Lumen Gentium, §25.
 See Vatican I, Pastor Aeternus, ch. 3.
 Bertone, “Magisterial Documents.”
 Pope John Paul II, Encyclical Letter Veritatis Splendor (1993), §115.
 Ibid., §81.
 Ibid., §79.
 Ibid., §82.
 Pope Paul VI, Solemni Hac Liturgia (1968), §3.
 Thomas Aquinas, Summa Theologiae [henceforth: ST] II-II, q. 1, a. 10.
 Paul VI, Solemni Hac Liturgia, §6.
 Ibid., §3.
 Interview with Cardinal Georges Cottier by Gianni Valente, “Paul VI, Maritain and the Faith of the Apostles,” 30 Days, no. 4 (2008).
 CIC, 749, §3.
 See Sullivan, Magisterium, 148–52.
 1983 CIC, can. 749, §3.
 See Francis A. Sullivan, “The ‘Secondary Object’ of Infallibility,” Theological Studies 54 (1993): 548–49.
 See Sullivan, Magisterium, 152.
 Ermenegildo Lio, Humanae Vitae e Infallibilità: il Concilio, Paolo VI e Giovanni Paolo II (Vatican City: Libreria Editrice Vaticana, l986).
 Pope Paul VI, Encyclical Letter Humanae Vitae (1968).
 Ibid., §6.
 Ibid., §4.
 All cited from Vatican II, Lumen Gentium, §25.
 CDF, Professio Fidei (1998).
 CDF, Donum Veritatis, §16.
 Mansi, 52:1226 B.
 Paul VI, Humanae Vitae, §4.
 Pope Pius XI, Divini Illius Magistri (1929), §18.
 Mansi, 52:1316 B.
 Paul VI, Humanae Vitae, §14.
 Cited by Brian W. Harrison, “The Ex Cathedra Status of the Encyclical Humanae Vitae,” Living Tradition 43 (Sep.–Nov., 1992), with reference to Jean-Marie Hervé, Manuale theologiae dogmaticae, vol. 1 (Paris: Berche & Pagis, 1935), 507.
 See L’Osservatore Romano (Italian), July 29/30, 1968.
 Harrison, “Ex Cathedra Status of the Encyclical Humanae Vitae.”
Dr. John Joy teaches Theology at St. Ambrose Academy in Madison, Wisconsin. In his spare time he also serves as President of the St. Albert the Great Center for Scholastic Studies and Managing Editor for the Aquinas Institute. His primary academic interests are in the theology and philosophy of St. Thomas Aquinas, dogmatic theology, and especially questions of infallibility and the magisterium of the Church. He is the author of On the Ordinary and Extraordinary Magisterium from Joseph Kleutgen to the Second Vatican Council (Muenster: Aschendorff, 2017) as well as various articles published in Nova et Vetera, Seminary Journal, New Blackfriars, and Antiphon.