The fundamental disagreement between Catholics and Protestants concerns the issue of authority. The Protestant position(s) is(are) often grouped under the label of “sola Scriptura.” One example of a definition of sola Scriptura can be found in the Westminster Confession of Faith (1646):
“The whole counsel of God, concerning all things necessary for his own glory, man’s salvation, faith, and life, is either expressly set down in Scripture, or by good and necessary consequence may be deduced from Scripture: unto which nothing at any time is to be added, whether by revelations of the Spirit, or traditions of men” .
Similarly, the Thirty-Nine Articles state:
“Holy Scripture containeth all things necessary to salvation: so that whatsoever is not read therein, nor may be proved thereby, is not to be required of any man, that it should be believed as an article of the Faith, or be thought requisite or necessary to salvation” .
For a more recent (1932) statement, we can look to the “Brief Statement of the Doctrinal Position of the Missouri Synod,” which reads:
“Hence the Holy Scriptures are the sole source from which all doctrines proclaimed in the Christian Church must be taken and therefore, too, the sole rule and norm by which all teachers and doctrines must be examined and judged” .
These three statements cover positions in the Reformed, Anglican, and Lutheran traditions. But what is the Catholic position? The Council of Trent in its Fourth Session declared:
“[Our] Lord Jesus Christ, the Son of God, first promulgated [the Gospel] with His own mouth, and then commanded to be preached by His Apostles to every creature, as the fountain of all, both saving truth, and moral discipline; and seeing clearly that this truth and discipline are contained in the written books, and the unwritten traditions which, received by the Apostles from the mouth of Christ himself, or from the Apostles themselves, the Holy Ghost dictating, have come down even unto us, transmitted as it were from hand to hand; (the Synod) following the examples of the orthodox Fathers, receives and venerates with an equal affection of piety, and reverence, all the books both of the Old and of the New Testament–seeing that one God is the author of both –as also the said traditions, as well those appertaining to faith as to morals, as having been dictated, either by Christ’s own word of mouth, or by the Holy Ghost, and preserved in the Catholic Church by a continuous succession” .
The Council of Trent, in contradistinction from the Protestant statements, thus declared that both written books of Scripture and “unwritten traditions” are to be received and venerated “with an equal affection of piety.” Both the written books and the unwritten traditions are from Christ or the Holy Spirit as their source, were received by the apostles, “have come down even unto us, transmitted as it were from hand to hand,” and have been “preserved in the Catholic Church by a continuous succession.”
In the Second Session of the First Vatican Council, it was stated as part of the profession of faith:
“Apostolic and ecclesiastical traditions and all other observances and constitutions of that same church I most firmly accept and embrace . . . Likewise I accept sacred scripture according to that sense which holy mother church held and holds, since it is her right to judge of the true sense and interpretation of the holy scriptures; nor will I ever receive and interpret them except according to the unanimous consent of the fathers” .
In the document “Dei Verbum” from the Second Vatican Council, it is written:
“In His gracious goodness, God has seen to it that what He had revealed for the salvation of all nations would abide perpetually in its full integrity and be handed on to all generations. Therefore Christ the Lord in whom the full revelation of the supreme God is brought to completion, commissioned the Apostles to preach to all men that Gospel which is the source of all saving truths and moral teaching, and to impart to them heavenly gifts. This Gospel had been promised in former times through the prophets, and Christ Himself had fulfilled it and promulgated it with His lips. This commission was faithfully fulfilled by the Apostles who, by their oral preaching, by example, and by observances handed on what they had received from the lips of Christ, from living with Him, and from what He did, or what they had learned through the prompting of the Holy Spirit. The commission was fulfilled, too, by those Apostles and apostolic men who under the inspiration of the same Holy Spirit committed the message of salvation to writing . . . . This sacred tradition, therefore, and Sacred Scripture of both the Old and New Testaments are like a mirror in which the pilgrim Church on earth looks at God . . . . Now what was handed on by the Apostles includes everything which contributes toward the holiness of life and increase in faith of the peoples of God; and so the Church, in her teaching, life and worship, perpetuates and hands on to all generations all that she herself is, all that she believes . . . . Through the same tradition the Church’s full canon of the sacred books is known, and the sacred writings themselves are more profoundly understood and unceasingly made active in her . . . . Hence there exists a close connection and communication between sacred tradition and Sacred Scripture. For both of them, flowing from the same divine wellspring, in a certain way merge into a unity and tend toward the same end. For Sacred Scripture is the word of God inasmuch as it is consigned to writing under the inspiration of the divine Spirit, while sacred tradition takes the word of God entrusted by Christ the Lord and the Holy Spirit to the Apostles, and hands it on to their successors in its full purity, so that led by the light of the Spirit of truth, they may in proclaiming it preserve this word of God faithfully, explain it, and make it more widely known. Consequently it is not from Sacred Scripture alone that the Church draws her certainty about everything which has been revealed. Therefore both sacred tradition and Sacred Scripture are to be accepted and venerated with the same sense of loyalty and reverence. Sacred tradition and Sacred Scripture form one sacred deposit of the word of God, committed to the Church . . . . It is clear, therefore, that sacred tradition, Sacred Scripture, and the teaching authority of the Church, in accord with God’s most wise design, are so linked and joined together that one cannot stand without the others, and that all together and each in its own way under the action of the one Holy Spirit contribute effectively to the salvation of souls” .
The above lengthy quotation articulates well the Catholic position regarding divine revelation. It is clear from these sources that Catholic theology holds that, in distinction from the written Scriptures, there are unwritten apostolic traditions which are equally authoritative and binding, because, like the Scriptures, they come from God as their source, and with the Scriptures form one deposit of revelation to be accepted by faith.
But what is the evidence for these unwritten apostolic traditions? Why should we think there were any such unwritten traditions handed on from the apostles in the first place? In this post, I hope to give an introductory outline of some of the answers to these questions.
The first place to look is Scripture itself, since both Catholics and Protestants accept Sacred Scripture as a genuine authority and source of divine revelation. Even apart from its status as authority/source for divine revelation, the documents of Scripture provide a historical look into the life, thinking, and beliefs of the early Church. They are, as such, an invaluable resource.
A central text for our considerations can be found in the Second Letter of St. Paul to the Thessalonians. In 2:15, St. Paul writes:
“So then, brethren, stand firm and hold to the traditions which you were taught by us, either by word of mouth or by letter” 
The “you” here is “the Church of the Thessalonians,” and the “us” is “Paul, Silvanus, and Timothy” (1:1). The latter three in the present text explicitly command the Thessalonian Christians to “hold to the traditions which you were taught by us, either by word of mouth or by letter.” In other words, the “traditions” given by St. Paul and the others to the Thessalonians were via two modes of transmission: spoken word or written word. And, again, the Thessalonian Christians are commanded to hold to the teachings from both modes of transmission, not simply one or the other.
Obviously Protestants are not unaware of this text; and there are at least two responses which can be given by them. One is that although in the apostolic age there were two modes of transmission, the content of the transmission was the same for both. In other words, the traditions which were handed on by the apostles orally were the same traditions as those handed on via writing; as such there were no teachings handed on orally which were not also contained in writing. A second option of response is that, although there were unwritten apostolic traditions which were distinct in content from the written apostolic teachings, these are not binding on Christians after the apostolic age, because the apostles are no longer here to preach them and there is no other means besides Scripture to reliably know what these traditions were.
I want to focus here on the first response, as my inquiry at present simply concerns whether there are unwritten apostolic traditions. This first response seems unlikely simply given the wording of the text. The Greek reads: εἴτε διὰ λόγου εἴτε δι’ ἐπιστολῆς ἡμῶν. The double “εἴτε . . . εἴτε” is an “either . . . or” construction. So the Thessalonians are commanded to hold to the traditions they have been taught, either by word, or by letter. The implication of the natural reading is that some traditions have been taught orally, and others have been taught via writing. I.e., that not all traditions have been given via only one mode of transmission. This makes sense, insofar as much more can be said in person than through writing, and in much more detail.
To show that the above is not simply a post-Tridentine, post hoc interpretation, let’s look at the comments of two pre-Tridentine doctors of the Church regarding this very text. First, from the thirteenth century we have the comments of the Angelic Doctor, Saint Thomas:
And they delivered these traditions in two ways. Some they delivered by words, and so he says, by word. Others they delivered in writing, and so he adds, or by our epistle. Hence it is clear that there are many things in the church which were not written and yet were taught by the apostles and so must be followed. For there were many things which the apostles judged were best hidden, as Dionysius says. Hence the Apostle says: the rest I will arrange when I come (1 Cor 11:34)” .
Saint Thomas also, in the Summa Theologiae, mentions what he takes to be one such unwritten tradition: the adoration of images of Christ. He says:
“The Apostles, led by the inward instinct of the Holy Ghost, handed down to the churches certain instructions which they did not put in writing, but which have been ordained, in accordance with the observance of the Church as practiced by the faithful as time went on. Wherefore the Apostle says (2 Thess. 2:14): “Stand fast; and hold the traditions which you have learned, whether by word”—that is by word of mouth—“or by our epistle”—that is by word put into writing. Among these traditions is the worship of Christ’s image” .
Second, let’s look at the comments of another ecclesial doctor, this time from the fourth/fifth centuries: Saint John Chrysostom. In his fourth homily on Second Thessalonians, commenting on the very verse in question, he writes:
“Hence it is manifest, that they did not deliver all things by Epistle, but many things also unwritten, and in like manner both the one and the other are worthy of credit. Therefore let us think the tradition of the Church also worthy of credit. It is a tradition, seek no farther” .
Here we have two great doctors and saints, almost a thousand years apart, both pre-Tridentine and one over a thousand years prior to the Reformation, interpreting the same text according to the interpretation I’ve indicated. But even if this text in itself were insufficient to establish the reality of unwritten apostolic traditions, it at the very least establishes the legitimacy of two modes of transmission of the apostolic teachings, at least in the apostolic age.
But, in fact, we also have other Scripture which indicates that the apostolic traditions were not all written. One such indication comes from a text already referenced in the first quote from Saint Thomas above: 1 Corinthians 11:34. St. Paul has just finished giving instructions concerning the celebration of the Eucharist, and he concludes: “About the other things I will give directions when I come” . Here we have a clear example of St. Paul, in a written letter, informing his audience that there are other directions which he will give to them, not in writing, but in person.
From these considerations it seems very evident to me that, at least in the apostolic age, there were both distinct modes of transmission for apostolic teachings, and distinct contents delivered via those modes. Now, the Protestant might claim that, while during the apostolic age the apostolic traditions were delivered via two modes, by the close of that age, all of the traditions had been written down in the texts of Scripture. The problem is that there is no obvious warrant from Scripture for this claim. All we have from Scripture is that there are unwritten teachings in addition to those contained in writing, as well as the command to abide by both sets of teachings. There is no hint that all unwritten teachings will necessarily be committed to writing or otherwise cease to be authoritative.
But I now wish to go even further, beyond the apostolic age, and ask whether the fathers of the church thought that there were unwritten apostolic traditions which had been passed down. The answer, I believe, is yes. We’ve already considered the evidence from St. John Chrysostom; let’s now look at others.
One very important early father is Saint Irenaeus (ca. 130-202 AD). Tradition and apostolic succession play an important role in the thought of this saint. To take on place in particular, we will look at some early chapters in the third book of his Adversus Haereses, written against the gnostic heresies. In III.2 he explains that when the gnostics are refuted from the Scriptures, they turn around and claim that the truth can only be known from a secret oral tradition known only to a select few. St. Irenaeus counters that this secret oral tradition is not genuine apostolic tradition but is rather “fiction of [their] own inventing” . He then contrasts their illegitimate tradition with real apostolic tradition:
“But, again, when we refer them to that tradition which originates from the apostles, [and] which is preserved by means of the succession of presbyters in the Churches, they object to tradition, saying that they themselves are wiser not merely than the presbyters, but even than the apostles, because they have discovered the unadulterated truth . . . . It comes to this, therefore, that these men do now consent neither to Scripture nor to tradition.” .
Notice that throughout the entire discussion of this chapter, St. Irenaeus nowhere denies the reality of apostolic traditions, nor its authority; and the entire line of thought presupposes and takes for granted the distinction between Scripture and tradition. The Scriptures are the writings, but the traditions are the teachings which 1) originate from the apostles, and 2) are “preserved by means of the succession of presbyters in the Churches.” The secret oral tradition of the heretics is rejected, not qua tradition, but insofar as it is not actually from the apostles and is not preserved or taught in the Church. Real apostolic tradition is that which is taught by the Church which has its succession from the apostles. St. Irenaeus reiterates this point by going on to say in the next chapter:
“It is within the power of all, therefore, in every Church, who may wish to see the truth, to contemplate clearly the tradition of the apostles manifested throughout the whole world; and we are in a position to reckon up those who were by the apostles instituted bishops in the Churches, and [to demonstrate] the succession of these men to our own times; those who neither taught nor knew of anything like what these [heretics] rave about . . . . In this order, and by this succession, the ecclesiastical tradition from the apostles, and the preaching of the truth, have come down to us. And this is most abundant proof that there is one and the same vivifying faith, which has been preserved in the Church from the apostles until now, and handed down in truth” .
And then in the next chapter he continues:
“Since therefore we have such proofs, it is not necessary to seek the truth among others which it is easy to obtain from the Church; since the apostles, like a rich man [depositing his money] in a bank, lodged in her hands most copiously all things pertaining to the truth: so that every man, whosoever will, can draw from her the water of life. For she is the entrance to life; all others are thieves and robbers. On this account are we bound to avoid them, but to make choice of the thing pertaining to the Church with the utmost diligence, and to lay hold of the tradition of the truth. For how stands the case? Suppose there arise a dispute relative to some important question among us, should we not have recourse to the most ancient Churches with which the apostles held constant intercourse, and learn from them what is certain and clear in regard to the present question? For how should it be if the apostles themselves had not left us writings? Would it not be necessary, [in that case,] to follow the course of the tradition which they handed down to those to whom they did commit the Churches?” .
Here we are told that even if the apostles had left us no writings, the truth could be known purely through the traditions which they handed down through the Church. This indicates that, again, for St. Irenaeus, tradition refers to something distinct from written Scripture, at least in mode if not in content. The above, as well as other things said in the same chapter, might seem to point to Scripture and tradition actually being the same in content; and indeed there can be no denying that for Irenaeus the essence of the two overlaps and intertwines. On his view, it seems that tradition includes the heart of the message of Scripture, according to its correct, apostolic interpretation. But there is no statement that the two are exactly identical in content, or that tradition is limited to the content of Scripture, or that the two are exactly coincident. At the very least we have indication here that the apostolic traditions — whatever those might contain — were preserved in the Church.
But there are indications from other fathers that apostolic traditions contain contents not found in Scripture. Saint Athanasius, another church doctor, writes in one of his letters, concerning the celebration of Easter:
“So we are not remiss in giving notice of its seasons, as we have received from the Fathers. Again we write, again keeping to the apostolic traditions, we remind each other when we come together for prayer; and keeping the feast in common, with one mouth we truly give thanks to the Lord. Thus giving thanks unto Him, and being followers of the saints, ‘we shall make our praise in the Lord all the day ,’ as the Psalmist says. So, when we rightly keep the feast, we shall be counted worthy of that joy which is in heaven” .
Notice that he seems to refer to rightly keeping the feast as “keeping to the apostolic traditions” which “we have received from the Fathers.” Thus Saint Athanasius, this pillar of orthodoxy, seems to regard the proper celebration of Easter as part of genuine apostolic tradition. But, of course, nothing of this is mentioned within the writings of Scripture. So it seems that Saint Athanasius regards the contents of apostolic tradition as extending beyond the confines of what is contained in Scripture.
Next we turn to Saint Basil the Great, yet another doctor. In his work De Spiritu Sancto he explains:
“Of the beliefs and practices whether generally accepted or publicly enjoined which are preserved in the Church some we possess derived from written teaching; others we have received delivered to usin a mysteryby the tradition of the apostles; and both of these in relation to true religion have the same force. And these no one will gainsay — no one, at all events, who is even moderately versed in the institutions of the Church. For were we to attempt to reject such customs as have no written authority, on the ground that the importance they possess is small, we should unintentionally injure the Gospel in its very vitals; or, rather, should make our public definition a mere phrase and nothing more” .
Here Saint Basil explicitly asserts that of both beliefs and practices, some are derived from written teachings, but others are received “in a mystery” from apostolic tradition; and both “have the same force.” Indeed, he even says that to reject “such customs as have no written authority” would be to “injure the Gospel in its very vitals.” What he seems to mean is that the unwritten apostolic traditions especially consist in practices of living the faith, especially in relation to sacramental life. Of course, without living the Gospel, the latter would be reduced to “a mere phrase and nothing more.” Thus he goes on, in discussing some of the unwritten traditions, to mention the sign of the cross, the words of invocation for the celebration of the Eucharist, and blessing the baptismal waters and the oil for chrism. With respect to the celebration of the Eucharist he says: “For we are not, as is well known, content with what the apostle or the Gospel has recorded, but both in preface and conclusion we add other words as being of great importance to the validity of the ministry, and these we derive from unwritten teaching” . And on the blessing of waters and oil, he says: “On what written authority do we do this? Is not our authority silent and mystical tradition?” . He goes on to explain further:
“In the same manner the Apostles and Fathers who laid down laws for the Church from the beginning thus guarded the awful dignity of the mysteries in secrecy and silence, for what is bruited abroad random among the common folk is no mystery at all. This is the reason for our tradition of unwritten precepts and practices, that the knowledge of our dogmas may not become neglected and contemned by the multitude through familiarity” .
Next let us look at what one of the most renowned of fathers and doctors has to say: Saint Augustine. On the issue of not rebaptizing those baptized by heretics, he writes:
“The custom, which is opposed to Cyprian, may be supposed to have had its origin in apostolic tradition, just as there are many things which are observed by the whole Church, and therefore are fairly held to have been enjoined by the apostles, which yet are not mentioned in their writings” .
Here yet again we see a distinction being drawn been the apostolic writings and the apostolic traditions; and we are told that there are “many things” which were “enjoined by the apostles” and yet are not contained in writing. Similarly he state elsewhere:
“As to those other things which we hold on the authority, not of Scripture, but of tradition, and which are observed throughout the whole world, it may be understood that they are held as approved and instituted either by the apostles themselves, or by plenary Councils, whose authority in the Church is most useful, e.g. the annual commemoration, by special solemnities, of the Lord’s passion, resurrection, and ascension, and of the descent of the Holy Spirit from heaven, and whatever else is in like manner observed by the whole Church wherever it has been established” .
Thus we see that Saint Augustine held that there are practices which are held not on the authority of Scripture but on that of unwritten tradition, which implies that apostolic tradition itself is authoritative apart from Scripture.
There is much that could be said and examined on this subject; but I think I shall conclude here for now. I’d like to make clear that I am aware that there are many passages I have not listed which might appear to point against the conclusion I have drawn. Such passages need to be assessed in conjunction with those of the kind I have quoted, in order to make a complete judgement. For now, however, I am simply trying to make a positive case for unwritten apostolic tradition. Perhaps in another post I will consider the contrary evidence. In any case, I think what I have said here, drawing from both Scripture and historical statements from the fathers of the early church, suffice to provide a good foundation for the view that there are unwritten apostolic traditions. Whether such traditions are authoritative for Christians today is another matter; here I have only tried to point to the existence of such traditions. I hope also that the evidence given above might help show that the Catholic position, whether correct or not, has a legitimate foundation in the thinking of the early church.
- Creeds of the Churches: A Reader in Christian Doctrine from the Bible to the Present. Edited by John H. Leith. Third edition, 1982. Louisville: John Knox Press, 1963. Page 195.
2. Ibid., 267.
7. Revised Standard Version – Second Catholic Edition.
9. ST III.25.3
11. Revised Standard Version – Second Catholic Edition.
16. Letter 2.7, https://www.newadvent.org/fathers/2806002.htm
17. De Spiritu Sancto, 27.66, https://www.newadvent.org/fathers/3203.htm
21. On Baptism, Against the Donatists, 5.23, https://www.newadvent.org/fathers/14085.htm
22. Letter 54.1, https://www.newadvent.org/fathers/1102054.htm
Many of these references were discovered from: https://www.churchfathers.org/apostolic-tradition