But as I argued here, that is a misunderstanding of what sola scriptura is, and what it denies. Such a characteriziation misrepresents the nature of the disagreement between Protestants and the Catholic Church on this subject. Here is what surprises most Protestants: The Catholic Church has just as high a view of Scripture as do Protestants. For Catholics, as for Protestants, the Bible is the inspired and infallible Word of God. Concerning the books of the Bible the first Vatican Council taught (De Catholica Fide 2.7):
These books the Church holds to be sacred and canonical not because she subsequently approved them by her authority after they had been composed by unaided human skill, nor simply because they contain revelation without error, but because, being written under the inspiration of the Holy Spirit, they have God as their author, and were as such committed to the Church.
And Pope Leo XIII, in section 20 of Providentissimus Deus, wrote:
But it is absolutely wrong and forbidden, either to narrow inspiration to certain parts only of Holy Scripture, or to admit that the sacred writer has erred. For the system of those who, in order to rid themselves of these difficulties, do not hesitate to concede that divine inspiration regards the things of faith and morals, and nothing beyond, because (as they wrongly think) in a question of the truth or falsehood of a passage, we should consider not so much what God has said as the reason and purpose which He had in mind in saying it-this system cannot be tolerated. For all the books which the Church receives as sacred and canonical, are written wholly and entirely, with all their parts, at the dictation of the Holy Ghost; and so far is it from being possible that any error can co-exist with inspiration, that inspiration not only is essentially incompatible with error, but excludes and rejects it as absolutely and necessarily as it is impossible that God Himself, the supreme Truth, can utter that which is not true. This is the ancient and unchanging faith of the Church, solemnly defined in the Councils of Florence and of Trent, and finally confirmed and more expressly formulated by the Council of the Vatican.
So if the Catholic Church affirms the inspiration and infallibilty of Scripture, then what is the difference between the Catholic and Protestant positions on the issue of sola scriptura? Let's take a look. The Catholic Church affirms that God has said everything in His Word, who is Christ, (CCC 65), and that there will be no further Revelation until the return of Christ. (CCC 66). According to the Catholic Church the revelation of Christ was given to the Apostles, who handed on the gospel of Christ in two ways: orally and in writing. (CCC 76) So one important difference between the Protestant sola scriptura position and that of the Catholic Church is that Protestants generally believe that whatever Christ wanted Christians to know was written down by the Apostles in the New Testament. Some Protestants claim that if the Apostles had thought something important for subsequent generations of Christians to know, they would have written it down. So, goes their reasoning, whatever the Apostles didn't write down must not have been necessary for us to know. The disagreement here between Protestants and Catholics is not about the authority of the Word of God. Both agree that the Word of God is the highest authority in the Church. (cf. CCC 86) The first disagreement relevant to sola scriptura concerns whether the Word of God was also handed down orally or not. The Catholic Church claims that Christ's gospel was handed down both orally and in writing (CCC 82), and Protestants deny that it was handed down orally (or claim that oral transmission cannot be trusted, and so in practice we cannot rely on the oral tradition). So one Protestant construal of the sola in sola scriptura is that the Word of God is found only in Scripture. According to this notion, the Word of God is not found anywhere else other than in Scripture.
But the second disagreement relevant to sola scriptura is no less important. It may be even more important. This disagreement concerns not *where* the Word of God is found (i.e. only in the Scripture), but *how* the Word of God is found. The Catholic Church teaches that in order to preserve the gospel, the Apostles left bishops as their successors and gave to these bishops their teaching authority, with the command to preserve this teaching authority through the laying on of hands in a continual succession until the end of time. (CCC 77) This living teaching authority is called the "Magisterium". According to the Catholic Church:
The task of giving an authentic interpretation of the Word of God, whether in its written form or in the form of Tradition, has been entrusted to the living teaching office of the Church alone. Its authority in this matter is exercised in the name of Jesus Christ." This means that the task of interpretation has been entrusted to the bishops in communion with the successor of Peter, the Bishop of Rome. (CCC 85)
The Protestant position, on the question of *how* the Word of God is to be found, is that Scripture is self-interpreting (this is called the perspicuity of Scripture)(cf. WCF 1.9), and that the Holy Spirit has the authoritative interpretation of Scripture (cf. WCF1.10). This is the second construal of the sola in the Protestant conception of sola scriptura. This way of conceiving sola scriptura implicitly denies that the Apostles established a perpetual living teaching authority in the Church. It does this by asserting implicitly that only the [Holy Spirit speaking through the] Scripture-interpreted Scripture is ultimately authoritative. Since the Holy Spirit (not any mere man) has the authoritative interpretation of Scripture, and since we all have equal access to the self-interpreting Scriptures and the Holy Spirit, therefore any claim that some body of mere men has the authoritative teaching concerning the gospel and the authoritative interpretation of Scripture is an encroachment (it is thought) upon Scripture's highest authority. The verse commonly used here is Acts 5:29, "We must obey God rather than men." If this manner of thought was good enough for the Apostles, then it is good enough for us.
So what lies behind this disagreement? The Catholic Church agrees that when what God says is contrary to what men are saying, we must obey God rather than those men. But what we are talking about here is how we know in the first place what it is exactly that God is saying. The Catholic Church teaches that it is through the Magisterium descended in sacramental succession from the Apostles that we may know in the first place what God is saying, just as Philip explained to the Ethiopian eunuch what the Scripture was saying. The Magisterium "is not superior to the Word of God, but is its servant." (CCC 86) Protestants, on the other hand, believe that ultimately it is through our own [Holy Spirit and Scripture assisted] interpretation of Scripture that we know what God is saying. Of course many Protestants believe in various doctrines promulgated by the early Ecumenical Councils, but they do so not because they think of these Councils as authoritative, as shown by the fact that they reject anything in them they think is unbiblical (i.e. contrary to their own interpretation of Scripture). They accept the teachings of Ecumenical Councils only insofar as what a council teaches accords with the individual Protestant's interpretation of Scripture. And "if I accept what an authority says only when that authority agrees with me, then my authority is me."
So what I want to point out here is that the disagreement between Protestants and the Catholic Church is not about the authority of Scripture. Protestants and the Catholic Church both agree about the divine and supreme authority of Scripture. The disagreement between Protestants and the Catholic Church regarding sola scriptura is about the authority of the Magisterium. The Catholic Church teaches that the Magisterium has teaching and interpretive authority; Protestants deny this, placing their own [Holy Spirit and Scripture assisted] interpretation of Scripture above the authority of the Magisterium. That belief necessarily underlies their justification for their departure from the Catholic Church in the sixteenth century. In this way sola scriptura is fundamentally a negative judgment, i.e. either there is no Magisterium or the Magisterium has no authority over my own personal interpretation of Scripture, as assisted by the Holy Spirit and Scripture itself.
What's behind this? I discussed monocausalism recently here, and I want to point out how it applies to this second construal of sola scriptura. (Both construals can be held at the same time, by the way.) Monocausalism is implicit in the notion that if men are speaking, then it cannot be the Holy Spirit who is speaking. Or, in addition, if mere men have such teaching and interpretive authority, then this must detract from the authority of the Scripture, or the Scripture and these men must be equal in authority. The two authorities (i.e. Magisterium and Scripture) are conceived of as in competition in some sense. To recognize the authority of the Magisterium is to exalt mere men to the status of the Word of God. And that is blasphemous and dishonoring to the Scriptures.
The flaw of this monocausal view of authority becomes more clear when we think about the role of the Apostles and how we got the New Testament. The Apostles were mere men, and yet their teaching and preaching and writing was authoritative. Their interpretation of their own writings was the authoritative interpretation of their own writings. The Holy Spirit was speaking through them in what they preached and wrote. To recognize the authority of the Apostles was not to exalt mere men to the status of the Word of God. And that was true of the bishops whom the Apostles appointed. The bishops appointed by the Apostles were not themselves Apostles, and their writings were not divinely inspired the way the writings of the Apostles were. But the bishops' interpretation of the Apostles' writings was authoritative for all Christians. Where in the early centuries do we find the idea of placing one's own interpretation above that of the teaching and interpretation of the bishops? In the practices of the heretics. (See here and here.) When the bishops spoke in unison, that was the authoritative teaching of the Church, and if you disagreed with it based on your own interpretation of Scripture, then ipso facto your interpretation was heretical. "Heretical" did not merely mean "contrary to my own interpretation of Scripture", it meant contrary to the authoritative teaching of the Church, as determined by the bishops in communion with the successor of St. Peter. And that has never changed.
The Protestant attempt to distinguish sola scriptura from solo scriptura fails, as I have argued here, precisely because without a Magisterium, sola scriptura necessarily reduces to solo scriptura. If ecclesial authority does not derive its authority sacramentally from the Apostles, then it derives its authority democratically, according to its agreement with our own interpretation of Scripture. And that is precisely the great error that St. Paul warned would arise in the end times, when men would gather around themselves teachers who taught according to what their itching ears wanted to hear. (2 Tim 4:3) It is the ecclesial consumerism of our time.
To doubt the Apostles was to doubt Christ. "He who listens to you listens to Me; he who rejects you rejects Me; but he who rejects Me rejects Him who sent Me." (Luke 10:16) That was just as true of the bishops appointed by the Apostles as it was of the Apostles themselves. In order to have faith in Christ, one had to listen to and trust the Apostles, the bishops they appointed, and the bishops whom those bishops appointed, etc. To doubt the Apostles was to lack faith. And so likewise, to doubt and distrust the bishops they appointed is to lack faith. Today is the feast day of St. Thomas the Apostle, sometimes called "doubting Thomas". He said, "Unless I see the nails marks in His hands and put my fingers where the nails where, and put my hand into His side, I will not believe it." (John 20:25) Jesus said to Thomas, "Because you have seen Me, you have believed; blessed are those who have not seen and yet have believed." (John 20:29) We are blessed who believe without having seen Jesus ourselves, but who believe on the basis of the testimony of those bishops in succession from the Apostles.
Sola scriptura is a formalization of a denial of the authority of the Magisterium, and thus a formalization of a lack of faith. It presents itself as exalting the authority of Scripture, but as I have shown, it has no higher view of Scripture than the Catholic Church has always had. In that way sola scriptura engages in false advertising, for it isn't what it advertises itself to be. It is essentially a denial of Magisterial authority, at best a lack of trust, at worst a form of rebellion. But it shouldn't surprise us that a form of rebellion would characterize itself as seeking to exalt God alone, for the chief rebel of all "masquerades as an angel of light". (2 Corinthians 11:14)
Lord Jesus, on this feast day of St. Thomas the Apostle, help our unbelief (Mark 9:24), that we may be one, as You and the Father are one.