Often, Catholics level a series of similar and related arguments at Protestants aiming to undermine the principle of sola scriptura and the private judgment Protestants employ to discern what is to be believed. For example, can Protestants agree on the essentials of Christianity, and can they even have “unity,” given that the different denominations—classically Lutheran, Reformed, Anglican, and Baptist—confess different things?
In response, the Protestant will point to various examples within the Catholic Church where profound disunity exists, such as the liturgy wars or dissident clergy who openly criticize the pope. Furthermore, it seems Catholics are also bound to use private judgment to identify the Catholic Church as trustworthy instead of other groups.
Are we all in the same boat, then? Is there no good argument to be leveraged against the Protestant doctrine of private judgment?
First, private judgment is the use of reason to deduce a new truth that is implicitly contained in another truth but was not previously explicit. Simply assenting to an express statement is not an act of private judgment. For example, assenting to the fact that Mary visited her cousin Elizabeth in Judah based on Luke 1:39-40 is merely an affirmative assent and not an exercise of private judgment, since no new conclusion is being made. This is not a point of dispute between Catholics and Protestants. Rather, examples of private judgment would include determining how Christ is present in the Eucharist from the words “this is my body” and John 6. Of the Catholic, Lutheran, and Reformed understandings of Christ’s presence, none is stated explicitly here, but must be deduced through reason.
Second, Scripture does not describe the Church as “united” in some vague or undefined sense, as though any kind of internal conflict—such as over liturgical practices or theological questions—were opposed to this unity. According to St. Paul, the Church is “one body” and has “one Lord, one faith, one baptism” (Eph. 4:4-5). Similarly, the Church Fathers and saints of the first century claim this property for the Church unambiguously. To list just two, consider St. Jerome:
The Bride, the sister, the mother, and whatever other titles you might think of—all refer to the one assembly of the Church, which is never without bridegroom, brother, or son. She has one faith: she is not corrupted by the variety of doctrines, nor torn apart by heresies. She remains a virgin. Wherever the Lamb goes, she follows him. She alone knows the Song of Christ (Against Jovinian, bk. 2, n. 19 [PL 23, 314C]).
Centuries later, St. Bede affirms the same:
Heretics are to be pursued and utterly crushed above all for this reason: lest their attacks divide the faith of the Church — which ought to be one — and drag it apart into factions *Allegorica expositio in Cantica canticorum, lib. 3 [PL 91, 1114]).
Do Protestants meet these criteria? They certainly share the same Lord as we do, and they likewise celebrate the same “one baptism.” But can they be said to share “one faith,” even among themselves?
Consider, for example, the Westminster Confession of Faith and the Lutheran Book of Concord. As its name implies, the former articulates what Reformed Christians confess as a matter of faith. The Lutheran Book of Concord states in its preface that it is “a declaration of our constant and perpetual, wish, and a repetition of our Christian faith and confession” (preface, n. 16). Indeed, its authors hoped that Catholic theologians at the time would cease making the accusation that the Lutherans “cannot decide among [themselves] upon anything as certain concerning [their] faith.”
Although these confessions agree on many things, like the Trinity and Christology, they do not agree on all of the articles they believe by faith, such as how Christ is present in the Eucharist or baptism. On the one hand, they extend the visible Church beyond the boundaries of any single denomination and include all denominations that preach the Gospel and administer the sacraments faithfully. Unlike Catholics, they do not believe that the visible Church has exclusive institutional bounds. On the other hand, they permit substantial disunity on articles of faith among groups they nevertheless consider within the same “body.”
If this is so, Protestants do not possess “one faith” as “one body,” contrary to the words of Paul and the Fathers. They share “one Lord” and “one baptism” but not “one faith.” Not only is this the case in fact, but a system like Protestantism cannot achieve the unity of faith in principle. Under sola scriptura, each believer retains the right of private judgment to determine whether a council, universal tradition, or confessional statement is consistent with Scripture. On that basis, he may accept or reject its teaching according to his own judgment. For example, the well-respected Scottish Reformed theologian Robert Baron wrote,
Scripture is the supreme judge of controversies . . . on matters of faith, according to which as a perfect rule both of faith, and of morals, both Ecclesiastical judges ought to judge, and inferiors or private persons, ought to examine their judgments or decrees (Apology for the Discussion on the Formal Object of Faith, Aberdeen, 1631, tr. 5, Auth. Dup., ch. 8, n. 6, p. 256-57).
Catholics do not retain this right regarding dogmatic definitions of faith. When the Council of Trent teaches that “in the sacrament of the most holy Eucharist are contained truly, really, and substantially, the body and blood together with the soul and divinity of our Lord Jesus Christ,” the Catholic is bound to give the assent of faith. Catholics cannot test the Council of Trent with Scripture when it infallibly teaches this.
Thus, the Catholic conception of the rule of faith is intrinsically ordered toward unity, for the members of the Church are bound to the same revealed truths by the same divine authority. Note how the Anglican theologian Richard Field compared the Catholic Church with the Protestant system of authority:
Our adversaries confess that the determination of the Church may make a truth to be Catholic—so that everyone must expressly believe it—that was not Catholic before. But we think that it is not the authority of the Church, but the clear deduction from the things which we are bound expressly to believe, that makes things of that sort such that they must be particularly and distinctly known and believed, though they were not necessarily so to be believed before: and therefore, before and without such determination, men seeing clearly the deduction of things of this nature from the former, and refusing to believe them, are condemned of heresy; and men not seeing that deduction, after the decree of a Council has passed upon them, may still doubt and refuse to believe, without being heretics (Of the Church, bk. 4, ch. 12).
Paul described his ministry as “bringing about the obedience of faith” (Rom. 1:5) and “taking every thought captive to obey Christ” (2 Cor. 10:5). By the ability to speak infallibly and authentically in God’s name, the Catholic Church has the means necessary to continue Paul’s mission and preserve the “unity of faith” (Eph. 4:13) among “all nations until the end of the age” (Matt. 28:19-20).
It should be obvious to anyone that a system that allows men to, as Field says, “still doubt and refuse to believe” as long as they are not convinced of something from Scripture will not attain the unity and uniformity of faith. More importantly, it cannot bring the minds of men into submission to God for the sake of his glory. Although Protestantism can bring people the gospel in its most basic form, it simply does not match the New Testament’s description of the Church’s ministry and unity of faith.
To this, Protestants may respond with several objections—in vain, since they miss the point of the argument.
1. Objection. Catholics likewise do not all profess the same faith in practice, since many laymen have never heard of certain dogmas and therefore have never believed them. Indeed, many even ignorantly deny them, such as the high number of people who do not believe in transubstantiation.
Reply: Neither Paul nor the holy Fathers were so naïve as to suppose that every individual Catholic must have explicit knowledge of every teaching of the Church and be free from ignorance concerning any of them. Such a standard would be unreasonable and, indeed, one that even Protestants do not apply to themselves. Instead, the faith of the Church refers to what is uniformly proposed for belief by the Church. St. Bonaventure says,
Some things must be believed implicitly, and others explicitly, insofar as faith necessary for salvation is concerned; for implicit faith can suffice for the faith of ordinary believers. . . .
Other articles of faith, however, which are less manifest, they are certainly bound to believe implicitly. By believing implicitly I mean that, in a general way, they believe everything that the holy Mother Church believes, so that, with respect to any particular article, they dissent from none of them and reject none of the articles of faith. . . .
When a simple man or an elderly woman hears some new teaching being preached, they ought not immediately to assent until they know that it is universally held by the Church (In Sent., lib. 3, dist. 25, a. 1, q. 3).
The fact that Protestants can recognize that a Catholic’s denial of transubstantiation is problematic shows that there is a definite dogmatic teaching concerning Christ’s presence in the Eucharist that Catholics are expected to believe. If someone wants to be a good and faithful Catholic, he will know what to believe.
Within Protestantism, different traditions propose different opposing things for belief, which, by definition, does not constitute “one faith.”
2. Objection. Catholic theologians disagree all the time, such as among the Dominicans, Franciscans, Jesuits, and other schools.
Reply. Again, these are theological schools and societies disputing over theological conclusions and opinions, not articles of faith. To be a Reformed Christian, you have to confess the faith in the Westminster Confession of Faith, which is opposed to some Lutheran articles of faith. There is no Thomistic or Franciscan confession of faith, but there is only one Catholic faith.
3. Objection. Protestants at least believe the essentials
Reply. Though this is mostly conceded, this distinction between essential articles of faith and non-essential articles is problematic. Obviously, certain doctrines are more essential than others in the role they play in our salvation, but insofar as they are articles of faith, they are all essential, since they are all revealed by God. As Cardinal Franzelin says, the assent of faith is not formally based on how proximate something is to salvation, but simply on the basis of God revealing.
There is one reasoning on account of which the formal object of faith is believed and whereby it is constituted in all revealed truths. This is certainly the authority of God speaking, or the speech of God being sufficiently proposed. The reasoning of belief is not claimed from the greater dignity, the innate necessity and the connection with the ultimate end of a truth which must be believed. Therefore all these pertain to properties of the thing which is believed, not to the motive and reasoning on account of which it is believed (On Divine Tradition, thesis 23).
Furthermore, Protestants introduce a distinction not made by Paul or the Fathers, who claim that the Church has “one faith” without qualifying the claim by excluding supposedly non-essential beliefs.
4. Objection. Catholics still have to privately judge the infallible teachings of their Church, so they do not escape this problem.
Reply. Although it is true that infallibility does not always guarantee clarity, the Church tends to be clear when it infallibly defines something in the context of a controversy. There is no doubt as to whether or not Mary was conceived without original sin, whether holy orders is a sacrament, whether the pope is infallible when speaking ex cathedra, etc. Simply assenting to these, just as one would assent to an express saying in Scripture, is not an exercise of private judgment.
Nevertheless, as the Code of Canon Law says, “No doctrine is understood as defined infallibly unless this is manifestly evident” (n. 749, §3).