My book, Rome's Audacious Claim, goes through the church fathers to refute the claim of Roman Catholic apologists that there was a pope in the first century. It explains how fourth-century events explain the rise of the papacy, the (later) development of Roman Catholicism, and then opens the door on the sordid results of Roman religious rule. Available where books are sold. See Amazon reviews.

Therefore, brothers, hold fast to the traditions which you have been taught, whether by word or by our letter. (2 Thess. 2:15)

Now I praise you, brothers, that you remember me in everything and keep the traditions as I delivered them to you. (1 Cor. 11:2)

The apostles have preached the Gospel to us from the Lord Jesus Christ; Jesus Christ [has done so] from God. … Having therefore received their orders … and thus preaching through countries and cities, they appointed the firstfruits [of their labours], having first proven them by the Spirit, to be bishops and deacons of those who should afterwards believe. … (ch. 42)

This was no mere earthly invention which was delivered to [Christians], nor is it a mere human system of opinion, which they judge it right to preserve so carefully, nor has a dispensation of mere human mysteries been committed to them, but truly God himself, who is almighty, the Creator of all things, and invisible, has sent from heaven, and placed among men the truth and the holy and incomprehensible Word, and has firmly established him in their hearts. (ch. 7)

This is he who, being from everlasting, is today called the Son. Through [him] the Church is enriched and grace … increases in the saints, furnishes understanding, revealing mysteries … by whom the limits of faith are not broken through, nor the boundaries set by the fathers passed over. Then the fear of the Law is chanted, the grace of the prophets is known, the faith of the Gospels is established, the tradition of the apostles is preserved, and the grace of the Church exults. (ch. 11)

Ignatius ... to the holy church which is at Tralles, beloved by God the Father, and Jesus Christ ... which also I salute in its [i.e., the church's] fulness, in the apostolic character, and wish abundance of happiness. (Letter to the Trallians, Introduction)

Whoever does not confess that Jesus Christ has come in the flesh is antichrist. Whoever does not confess the testimony of the cross is of the devil. Whoever perverts the oracles of the Lord to his own lusts and says that there is neither a resurrection nor a judgment, he is the firstborn of Satan. Therefore, let us forsake the vanity of many, and their false doctrines, and let us return to the word which has been handed down to us from the beginning. (Letter to the Philippians 7)

As I have already observed, the Church, having received this preaching and this faith, although scattered throughout the whole world, yet, as if occupying but one house, carefully preserves it. (Against Heresies I:10:2)

Nor will any one of the rulers in the churches, however highly gifted he may be in point of eloquence, teach doctrines different from these, for no one is greater than the Master; nor, on the other hand, will he who is deficient in power of expression inflict injury on the tradition. For the faith being ever one and the same, neither does one who is able at great length to discourse regarding it, make any addition to it, nor does one, who can say but little diminish it.

   It does not follow because men are endowed with greater and less degrees of intelligence, that they should therefore change the subject-matter [of the faith] itself. (Against Heresies I:10:2-3)

But, again, when we refer [the gnostics] to that tradition which originates from the apostles, which is preserved by means of the succession of elders in the churches, they object to tradition, saying that they themselves are wiser not merely than the elders, but even than the apostles. (Against Heresies III:2:2)

For if the apostles had known hidden mysteries, which they were in the habit of imparting to "the perfect" apart from and privately from the rest, they would have delivered them especially to those to whom they were also committing the churches themselves. For they wanted these men to be very perfect and blameless in all things, whom also they were leaving behind as their successors, delivering up their own place of government to these men; which men, if they discharged their functions honestly, would be a great boon, but if they should fall away, the direst calamity. (Against Heresies III:3:1)

Since, however, it would be very tedious, in such a volume as this, to reckon up the successions of all the Churches, we do put to confusion all those who … assemble in unauthorized meetings: one, by indicating that tradition derived from the apostles, of the very great, the very ancient, and universally known church founded and organized at Rome by the two most glorious apostles, Peter and Paul, and two, by the faith preached to men, which comes down to our time by means of the successions of the bishops. For to this church [Rome], on account of its more powerful preeminence, it is necessary that every church (that is, those who are on every side faithful) resort; in which church ever, by those who are on every side, has been preserved that tradition which is from the apostles. …

   [Here Irenaeus gives the succession from Peter through Linus, Anacletus, Clement and nine others down to his time.]

   … 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. (Against Heresies III:3:2)

Polycarp also was not only instructed by apostles and conversed with many who had seen Christ, but was also, by apostles in Asia, appointed bishop of the Church in Smyrna … [He]  departed this life, having always taught the things which he had learned from the apostles, and which the Church has handed down, and which alone are true. To these things all the Asiatic Churches testify, as do also those men who have succeeded Polycarp down to the present time … Then again, the church in Ephesus, founded by Paul and having John remaining with them permanently until the times of Trajan [began his reign in A.D. 98], is a true witness of the tradition of the apostles. (Against Heresies III:3:4)

Suppose there arises a dispute relative to some important question among us. Shouldn't we have recourse to the most ancient churches with which the apostles held constant interaction and learn from them what is certain and clear concerning the present question?

   How would it be if the apostles had not left us writings? Would it not be necessary to follow the course of tradition which they handed down to those [elders] to whom they committed the churches?

   Many nations of the barbarians who believe in Christ assent to this course. They have salvation written in their hearts without paper or ink. Carefully preserving the tradition, they believe in one God … by means of Jesus Christ, the Son of God …

   Those who, in the absence of written documents, have believed this faith are barbarians as regards our language, but concerning doctrine, manner, and tenor of life, they are, because of faith, very wise indeed. …

   If anyone were to preach to these men the inventions of the heretics [i.e., the gnostics], speaking to them in their native languages, they would immediately stop their ears and flee as far as possible. They would not endure even to hear their blasphemous speech.

   Thus, by means of that ancient tradition of the apostles, they do not allow their mind to conceive any part of the pompous words of these teachers, among whom neither church nor doctrine has ever been established. (Against Heresies III:4:1-2)

The preaching of the Church is true and stedfast, in which one and the same way of salvation is shown throughout the whole world. For to her is entrusted the light of God, and therefore the "wisdom" of God, by means of which she saves all men … For the Church preaches the truth everywhere, and she is the seven-branched candlestick which bears the light of Christ.

   Those, therefore, who desert the preaching of the Church, call in question the knowledge of the holy presbyters … such are all the heretics, and those who imagine that they have hit upon something more beyond the truth. (Against Heresies V:20:1-2)

Flee to the Church, and be brought up in her bosom, and be nourished with the Lordís Scriptures. For the Church has been planted as a garden in this world; therefore says the Spirit of God, "You may freely eat from every tree of the garden," that is, Eat ye from every Scripture of the Lord; but ye shall not eat with an uplifted mind, nor touch any heretical discord. (Against Heresies V:20:2)

That this rule of faith has come down to us from the beginning of the gospel, even before any of the older heretics, much more before Praxeas, a pretender of yesterday, will be apparent both from the lateness of date which marks all heresies, and also from the absolutely novel character of our new-fangled Praxeas. In this principle also we must henceforth find a presumption of equal force against all heresies whatsoever: that whatever is first is true, whereas that is spurious which is later in date. But keeping this prescriptive rule inviolate, still some opportunity must be given for review [i.e., examination by the Scriptures], with a view to the instruction and protection of various persons; were it only that it may not seem that each perversion of the truth is condemned without examination and simply prejudged. (Against Praxeas 2)

We … are not permitted to cherish any doctrine after our own will, nor to choose that which another person has introduced from their own private fancy. In the Lord's apostles we possess our authority. Even they did not choose to introduce anything from themselves, but faithfully delivered to the nations the discipline which they had received from Christ. If, therefore, even an angel from heaven should preach any other gospel, he would be called accursed by us. (Prescription Against Heretics 6)

From what and through whom and from when and to whom has been handed down that rule by which men become Christians? For wherever it is apparent that the true Christian rule and faith shall be, there will likewise be the true Scriptures and expositions thereof and all the Christian traditions. (Prescription Against Heretics 19)

Christ Jesus our Lord (May he bear with me a moment in how I have to say this!), whoever he is, of whatever God he is the Son, of whatever substance he is both man and God, of whatever faith he is the teacher, of whatever reward he is the promiser—[no matter what of these is true,] he did, while he lived on earth, personally declare who he was, what he used to be, what the Father's will was that he was administering, and what duty of man he was prescribing. [He declared this] either openly to the people, privately to his disciples, …whom he destined to be the teachers of the nations.

   Accordingly, after one of these were struck down, he commanded the eleven others … to go and teach all nations … Immediately, therefore, the apostles did that, whose title means "the sent ones." … They obtained the promised power of the Holy Spirit for the gift of miracles and of speech. After they first bore witness to faith in Jesus Christ throughout Judea and founding churches, they next went out into the world and preached the same doctrine of faith to the nations. As in Judea, they founded churches in every city, from which all other churches—one after another—derived the tradition of the faith and the seeds of doctrine and are every day deriving them so that they may be churches.

   In fact, it is for this reason only that they will be able to deem themselves apostolic; since, they are the offspring of apostolic churches. Every sort of thing must necessarily revert to its original for its classification. Therefore, the churches, although there are so many and so great, comprise but the one primitive church, by the apostles from whom they all spring. In this way all are primitive, all are apostolic, while they are proven to be one in unity by their peaceful fellowship, title of brotherhood, and bond of hospitality—privileges bestowed by no other rule than the one tradition of the same mystery. (Prescription Against Heretics 20)

From this, therefore, do we draw up our rule. Since the Lord Jesus Christ sent the apostles to preach, no others ought to be received as preachers than those whom Christ appointed … Nor does the Son seem to have revealed [the Father] to any other than the apostles, whom he sent forth to preach … What that was which they preached … can … properly be proven in no other way than by those very churches which the apostles founded in person, by declaring the Gospel directly to them themselves, both viva voce, as the phrase is, and afterwards by their letters.

   If, then, these things are so, it is equally apparent that all doctrine which agrees with the apostolic churches, those molds and original sources of the faith, must be reckoned for truth, as undoubtedly containing that which the churches received from the apostles, the apostles from Christ, and Christ from God. In the same way, all doctrine must be prejudged as false which savors of disagreement with the truth of the church and apostles of Christ and God. …

   We have fellowship with the apostolic churches because our doctrine is not in any way different from theirs. This is our witness of truth. (Prescription Against Heretics 21)

Let's suppose, then, that all [apostolically-founded churches] have erred … that the Holy Spirit had no such respect to any one [church] as to lead it into truth, although sent with this view by Christ … Is it likely that so many churches, and they so great, should have gone astray into one and the same faith? No casualty distributed among many men issues in one and the same result. Error of doctrine in the churches must necessarily have produced various issues. When, however, that which is deposited among many is found to be one and the same, it is not the result of error, but of tradition. Can anyone, then, be reckless enough to say that they were in error who handed on the tradition? (Prescription Against Heretics 28)

Truth had to wait for certain Marcionites and Valentinians to set it free [this is sarcasm]. During the interval the gospel was wrongly preached; men wrongly believed; so many thousands were wrongly baptized; so many works of faith were wrongly wrought; so many miraculous gifts, so many spiritual endowments, were wrongly set in operation; so many priestly functions, so many ministries, were wrongly executed; and, to sum up the whole, so many martyrs wrongly received their crowns! Else, if not wrongly done, and to no purpose, how comes it to pass that the things of God were on their course before it was known to what God they belonged? That there were Christians before Christ was found? That there were heresies before true doctrine? Not so! For in all cases truth precedes its copy, the likeness succeeds the reality. (Prescription Against Heretics 29)

If no passage of Scripture has prescribed [not wearing laurel crowns], assuredly custom, which without doubt flowed from tradition, has confirmed it. For how can anything come into use if it has not been first handed down?

   Even in pleading tradition, written authority—you say—must be demanded. Let us inquire, therefore, whether tradition, unless it be written, should not be admitted.

   Certainly we s hall say that it ought not to be admitted, if we maintain no cases of other practices on the ground of tradition alone ... I shall begin with baptism. When we are going to enter the water, just a little before ... we solemnly profess that we disown the devil, his pomp, and his angels. At that point, we are immersed three times, making a somewhat ampler pledge than the Lord has appointed in the Gospel. Then, when we are taken up, we taste first of all a mixture of milk and hone, and from that day we refrain from the daily bath for a whole week.

   In congregations before daybreak we also take, and from the hand of none but the presidents, the sacrament of the Eucharist, which the Lord both commanded to be eaten at meal times and enjoined to be taken by all alike.

   As often as the anniversary comes round, we make offerings for the dead as birthday honors. We count fasting or kneeling in worship on the Lord's day to be unlawful. We rejoice in the same privilege also from Passover to Whitsunday (Pentecost). We feel pained should any wine or bread, even though our own, be cast upon the ground. At every forward step and movement, at every going in and out, when we put on our clothes and shoes,  when we bathe, when we sit at table, when we light the lamps, on couch, on seat, in all the ordinary actions of life, we trace upon the forehead the sign [of the cross].  (De Corona 3)

   If, for these and other such rules, you insist upon having positive Scripture injunction, you will find none. Tradition will be held forth to you as the originator of them, custom as their strengthener, and faith as their observer. That reason will support tradition, and custom, and faith, you will either yourself perceive, or learn from some one who has. Meanwhile you will believe that there is some reason to which submission is due. (De Corona 4)

Let nothing be innovated, says [Stephen, bishop of Rome], nothing maintained, except what has been handed down. From where is [his] tradition? Does it descend from the authority of the Lord and the Gospel or does it come from the commands and letters of the apostles? For that those things which are written must be done, God witnesses and admonishes, saying to Joshua … "The book of this Law shall not depart from your mouth, but you shall meditate on it day and night so that you may be careful to do all that is written in it" [Josh. 1:8]. Also, the Lord, when he sent his apostles, commands that the nations should be baptized and taught to observe all that he commanded. If, therefore, it is either prescribed in the Gospel or contained in the letters or Acts of the apostles,that those who came from any heresy should not be baptized, but only hands laid on them to repentance, let this divine and holy tradition be observed. But if everywhere heretics are called nothing other than adversaries and antichrists, if they are pronounced as people to be avoided, twisted and condemned by themselves, why is it that they should not be found worthy to be condemned by us, since it is obvious by the apostolic testimony that they are condemned by themselves? So no one ought to defame the apostles as though they had approved of the baptism of heretics, or had taken communion with them without the Church's baptism, when they, the apostles, wrote such things about the heretics.

   … If in time past it was never at all prescribed nor written that only hands should be laid upon a heretic for repentance, and that with only this we may take communion with him; and if there is only one baptism, which … is granted of the divine condescension to the Church alone, then what obstinacy is it, or what presumption, to prefer human tradition to divine ordinance, and not to observe that God is indignant and angry as often as human tradition relaxes and passes by the divine precepts? As he cries out and says by Isaiah the prophet, "This people honoureth me with their lips, but their heart is far from me. In vain do they worship me, teaching the doctrines and commandments of men." (Letter to Pompeius, Letter 73:2-3 in The Ante-Nicene Fathers, vol. V)

We have heard that certain [men], wishing to oppose [the Nicene Creed] are attempting to cite a synod supposed to be held at Ariminum and are eagerly striving that it should prevail ... this is nothing else but a second growth of the Arian heresy. ... They were not afraid of God, who says, "Remove not the eternal boundaries which your fathers placed" [Prov. 22:28], and, "The one that speaks against father or mother, let him die the death" [Ex. 21:17]. They were not in awe of their fathers, who enjoined that they who hold the opposite of their confession should be anathema. (Synodal Letter to the Bishops of Africa)

We come now to the Vincentian Canon: “In the Catholic Church itself, every care should be taken to hold fast to what has been believed everywhere, always, and by all” (Commonitories 2 [p. 270]). This sentence is often shortened into the phrase “everywhere, always, and by all.” If you want good theology, look to the ancient Catholic Church, spread throughout the world and continuous over time. Any point of doctrine that clearly doesn’t meet the standards of the Canon—having been believed everywhere, always, and by all— should be treated with great suspicion. If the doctrine in question was part of original Christian teaching, why was it not preserved by the historic Catholic Church? (Doherty, D. "An Ancient Strategy for Rooting Out Bad Theology." Web. Echoes in the Catacombs. June 4, 2018.)

It is dangerous and terrible to hear or believe anything against the unanimous testimony of the entire holy Christian Church as held from the beginning for now over fifteen hundred years in all the world. (As quoted by Philip Schaff, History of the Christian Church, vol. VIII, ch. 13, sec. 99)

I am conquered by the Holy Scriptures quoted by me, and my conscience is bound in the word of God: I can not and will not recant any thing, since it is unsafe and dangerous to do any thing against the conscience. (At the Diet of Worms, as quoted by Schaff, ibid., vol. VII, ch. 3, sec. 55)

At first there was question only of traditions claiming a Divine origin, but subsequently there arose questions of oral as distinct from written tradition, in the sense that a given doctrine or institution is not directly dependent on Holy Scripture as its source but only on the oral teaching of Christ or the Apostles. ...

     Now in this respect there are several points of controversy between Catholics and every body of Protestants. Is all revealed truth consigned to Holy Scripture? or can it, must it, be admitted that Christ gave to His Apostles to be transmitted to His Church, that the Apostles received either from the very lips of Jesus or from inspiration or Revelation, Divine instructions which they transmitted to the Church and which were not committed to the inspired writings? ("Tradition and Living Magisterium", accessed 12/19/2011)

The strength of oral tradition is that the community protects the tradition ... from being changed because so many people are aware of what was faithfully passed onto them. The more people that know something the better it can be protected from change especially so in oral cultures where the information wasn't passed on in isolation but as part of a community. (The Failed Atheist blog; "Oral Tradition of the Gospels and Justin Bieber"; July 7, 2011)

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