The Fathers, Councils and Popes speak on Tradition
To make sure that the apostolic Tradition would be passed down after the deaths of the apostles, Paul told Timothy: "What you have heard from me before many witnesses entrust to faithful men who will be able to teach others also" (2 Tim. 2:2). In this passage he refers to the first four generations of apostolic succession--his own generation, Timothy's generation, the generation Timothy will teach, and the generation they in turn will teach.
The early Church fathers, who were links in that chain of succession, recognized the necessity of the Traditions that had been handed down from the Apostles and guarded them scrupulously, as the following quotations show.
Pope Clement I"Then the reverence of the law is chanted, and the grace of the prophets is known, and the faith of the Gospels is established, and the Tradition of the Apostles is preserved, and the grace of the Church exults" (Letter to the Corinthians 11 [A.D. 80]).
Papias"Papias [A.D. 120], who is now mentioned by us, affirms that he received the sayings of the Apostles from those who accompanied them, and he moreover asserts that he heard in person Aristion and the presbyter John. Accordingly he mentions them frequently by name, and in his writings gives their Traditions [concerning Jesus]. . . . [There are] other passages of his in which he relates some miraculous deeds, stating that he acquired the knowledge of them from Tradition" (Fragment in Eusebius, Church History 3:39 [A.D. 312]).
Eusebius of Caesarea"At that time [A.D. 150] there flourished in the Church Hegesippus, whom we know from what has gone before, and Dionysius, bishop of Corinth, and another bishop, Pinytus of Crete, and besides these, Philip, and Apolinarius, and Melito, and Musanus, and Modestus, and finally, Irenaeus. From them has come down to us in writing, the sound and orthodox faith received from Tradition" (Church History 4:21).
Irenaeus of Lyons"As I said before, the Church, having received this preaching and this faith, although she is disseminated throughout the whole world, yet guarded it, as if she occupied but one house. She likewise believes these things just as if she had but one soul and one and the same heart; and harmoniously she proclaims them and teaches them and hands them down, as if she possessed but one mouth. For, while the languages of the world are diverse, nevertheless, the authority of the Tradition is one and the same" (Against Heresies 1:10:2 [A.D. 189]).
Irenaeus of Lyons"That is why it is surely necessary to avoid them [heretics], while cherishing with the utmost diligence the things pertaining to the Church, and to lay hold of the Tradition of truth. . . . What if the Apostles had not in fact left writings to us? Would it not be necessary to follow the order of Tradition, which was handed down to those to whom they entrusted the Churches?" (ibid., 3:4:1).
Irenaeus of Lyons"It is possible, then, for everyone in every church, who may wish to know the truth, to contemplate the Tradition of the Apostles which has been made known throughout the whole world. And we are in a position to enumerate those who were instituted bishops by the Apostles and their successors to our own times--men who neither knew nor taught anything like these heretics rave about.
"But since it would be too long to enumerate in such a volume as this the successions of all the churches, we shall confound all those who, in whatever manner, whether through self-satisfaction or vainglory, or through blindness and wicked opinion, assemble other than where it is proper, by pointing out here the successions of the bishops of the greatest and most ancient church known to all, founded and organized at Rome by the two most glorious Apostles, Peter and Paul, that church which has the Tradition and the faith which comes down to us after having been announced to men by the Apostles.
"With this church, because of its superior origin, all churches must agree--that is, all the faithful in the whole world--and it is in her that the faithful everywhere have maintained the Apostolic Tradition" (ibid., 3:3:1-2).
Eusebius of Caesarea"A question of no small importance arose at that time [A.D. 190]. For the parishes of all Asia . . . held that the fourteenth day of the moon, on which day the Jews were commanded to sacrifice the lamb, should be observed as the feast of the Savior's Passover. . . . But it was not the custom of the churches in the rest of the world to end it at this time, as they observed the practice which, from Apostolic Tradition, has prevailed to the present time, of terminating the fast [of Lent] on no other day than on that of the resurrection of our Savior [Sunday]" (Church History 4:23).
Clement of Alexandria"Well, they preserving the Tradition of the blessed doctrine derived directly from the holy Apostles, Peter, James, John, and Paul, the sons receiving it from the father (but few were like the fathers), came by God's will to us also to deposit those ancestral and apostolic seeds. And well I know that they will exult; I do not mean delighted with this tribute, but solely on account of the preservation of the truth, according as they delivered it. For such a sketch as this, will, I think, be agreeable to a soul desirous of preserving from loss the blessed Tradition" (Miscellanies 1:1 [A.D. 208]).
Origen"Although there are many who believe that they themselves hold to the teachings of Christ, there are yet some among them who think differently from their predecessors. The teaching of the Church has indeed been handed down through an order of succession from the Apostles and remains in the churches even to the present time. That alone is to be believed as the truth which is in no way at variance with ecclesiastical and Apostolic Tradition" (The Fundamental Doctrines 1:2 [A.D. 225]).
Cyprian of Carthage"[T]he Church is one, and as she is one, cannot be both within and without. For if she is with Novatian, she was not with [Pope] Cornelius. But if she was with Cornelius, who succeeded the bishop Fabian by lawful ordination, and whom, beside the honor of the priesthood, the Lord glorified also with martyrdom, Novatian is not in the Church; nor can he be reckoned as a bishop, who, succeeding to no one, and despising the evangelical and Apostolic Tradition, sprang from himself. For he who has not been ordained in the Church can neither have nor hold to the Church in any way" (Letters 75:3 [A.D. 253]).
Pope Saint Stepehen I
"Let them innovate in nothing, but keep the traditions".
Athanasius"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" (Festal Letters 2:7 [A.D. 330]).
Athanasius " Catholics who remain faithful to Tradition, even if they are reduced to a handful, are the true Church of Jesus Christ." (ca. 296-373) Apud Caillau and Guillou, Coll. Selecta Ss. Eccl. Patrum, vol. 32, pp. 411-412
Athanasius"But you are blessed, who by faith are in the Church, dwell upon the foundations of the faith, and have full satisfaction, even the highest degree of faith which remains among you unshaken. For it has come down to you from Apostolic Tradition, and frequently accursed envy has wished to unsettle it, but has not been able" (ibid., 29).
Basil the Great"Of the dogmas and messages preserved in the Church, some we possess from written teaching and others we receive from the Tradition of the Apostles, handed on to us in mystery. In respect to piety both are of the same force. No one will contradict any of these, no one, at any rate, who is even moderately versed in matters ecclesiastical. Indeed, were we to try to reject unwritten customs as having no great authority, we would unwittingly injure the gospel in its vitals; or rather, we would reduce [Christian] message to a mere term" (The Holy Spirit 27:66 [A.D. 375]).
Papal Coronation Oath
"I vow ... to change nothing of the received Tradition, and nothing thereof I have found before me guarded by my God-pleasing predecessors, to encroach, to alter, or to permit any innovation therein." 678 AD
Epiphanius of Salamis"It is needful also to make use of Tradition, for not everything can be gotten from Sacred Scripture. The holy Apostles handed down some things in the Scriptures, other things in Tradition." (Medicine Chest Against All Heresies 61:6 [A.D. 375]).
Augustine"But the admonition that he [Cyprian] gives us, 'that we should go back to the fountain, that is, to Apostolic Tradition, and thence turn the channel of truth to our times,' is most excellent, and should be followed without hesitation" (ibid., 5:26).
John Chrysostom"[Paul commands:] 'Therefore, brethren, stand fast and hold the Traditions which you have been taught, whether by word or by our letter' [2 Thess. 2:15]. From this it is clear that they did not hand down everything by letter, but there is much also that was not written. Like that which was written, the unwritten too is worthy of belief. So let us regard the Tradition of the Church also as worthy of belief. Is it a Tradition? Seek no further" (Homilies on 2 Thessalonians [A.D. 402]).
"The best advice I can give you is this. Church traditions -- especially when they do not run counter to the Faith -- are to be observed in the form in which previous generations have handed them down". Letters, Fourth Century:
Pope St. Leo the Great,
"Teach nothing new, but implant in the hearts of everyone those things which the fathers of venerable memory taught with a uniform preaching ... Whence, we preach nothing except what we have received from our forefathers. In all things, therefore, both in the rule of faith in the observance of discipline, let the pattern of antiquity be observed."
Vincent of Lerins"The Church of Christ, zealous and cautious guardian of the dogmas deposited with it, never changes any phase of them. It does not diminish them or add to them; it neither trims what seems necessary now grafts things superfluous . . . but it devotes all its diligence to one aim: To treat tradition faithfully and wisely; to consolidate and to strengthen what already was clear; and to guard what already was confirmed and defined. . . . . What then shall the Catholic do if some portion of the Church detaches itself from communion of the universal Faith? What other choice can he make? And if some new contagion attempts to poison, no longer a small part of the Church, but the whole Church at once, then his great concern will be to attach himself to antiquity which can no longer be led astray by any lying novelty". Commonitoria (died ca. 445 A.D.:)
Pope Agatho"And briefly we shall intimate to [you], what the strength of our Apostolic faith contains, which we have received through Apostolic Tradition and through the Tradition of the apostolical Pontiffs, and that of the five holy general synods [ecumenical councils], through which the foundations of Christ's Catholic Church have been strengthened and established" (Letter read at fourth session of III Constantinople [A.D. 680]).
Pope Agatho"For this is the rule of the true faith, which this spiritual mother of your most tranquil empire, the Apostolic Church of Christ, has both in prosperity and in adversity always held and defended with energy; which, it will be proved, by the grace of Almighty God, has never erred from the path of the Apostolic Tradition, nor has she been depraved by yielding to heretical innovations, but from the beginning she has received the Christian faith from her founders, the princes of the Apostles of Christ, and remains undefiled unto the end, according to the divine promise of the Lord and Savior himself" (ibid.).
Pope Agatho"[T]he Holy Church of God . . . has been established upon the firm rock of this Church of blessed Peter, the Prince of the Apostles, which by his grace and guardianship remains free from all error, [and possesses that faith] the whole number of rulers and priests, of the clergy and of the people, unanimously should confess and preach with us as the true declaration of the Apostolic Tradition, in order to please God and to save their own souls"" (ibid.).
St. Isidore-, extraordinary Doctor of the Church and last of the great Latin Fathers:
"Therefore, heresy is from the Greek word meaning 'choice' . . . . But we are not permitted to believe whatever we choose, nor to choose whatever someone else has believed. We have the Apostles of God as authorities, who did not . . . choose what they would believe but faithfully transmitted the teachings of Christ. So, even if an angel from heaven should preach otherwise, he shall be called anathema. -Etymologies (7th Century)
St. Thomas Aquinas
"'One faith,' St. Paul writes (Eph. 4:5). Hold most firmly that our faith is identical with that of the ancients. Deny this, and you dissolve the unity of the Church ... We must hold this for certain, namely: that the faith of the people at the present day is one with the faith of the people in past centuries. Were this not true, then we would be in a different church than they were in and, literally, the Church would not be One."
“It is absurd and a detestable shame that we should suffer those traditions to be changed that we have received from the Fathers of old,” - Summa Theologica, II, I, Q. 97, art. 2 (quoting the Decretals).
Second Council of Nicea
"If anyone rejects all ecclesiastical tradition, whether written or unwritten, let him be anathema".
"Those therefore who after the manner of wicked heretics dare to set aside ecclesiastical traditions, and to invent any kind of novelty, or to reject any of those things entrusted to the Church, or who wrongfully and outrageously devise the destruction of any of those traditions enshrined in the Catholic Church, are to be punished thus: if they are bishops, we order them to be deposed, but if they are monks or laypersons, we command them to be excluded from the community."
The Council of Trent
"The true Church is also to be known from Her origin, which She derives under the law of grace from the Apostles; for Her doctrines are neither novel nor of recent origin, but were delivered of old by the Apostles and disseminated throughout the world." -- (16th Century)
First Vatican Council (1869-1870)
"For the Holy Spirit was not promised to the successors of Peter, that by His revelation they might make known new doctrine, but that by His assistance they might inviolably keep and faithfully expound the revelation or deposit of faith delivered through the Ages."
Pope St. Puis X :
"The true friends of the people are neither innovators, nor revolutionaries, but traditionalists" - Letter on the Sillon, 25 August 1910
"So then, brethren, stand firm and hold to the Traditions which you were taught by us, either by word of mouth or by letter" - 2 Thess. 2:15