I made some errors in interpretation of Against Heresies 3.4.1 and instead of rehashing everything I got specifically wrong, I am going to re-present how I understand Irenaeus’ point in 3.1-5 to the best of my ability.

Ed: This was made when I was a Protestant and upon greater learning and reflection my thoughts have evolved.

As a summary of what I understand to be his overall thought process, I am going to quote Athanasius who in my mind made the same exact point for the same exact reason. In his 59th letter he writes:

1. For the Faith there confessed by the Fathers according to the divine Scriptures is enough by itself at once to overthrow all impiety, and to establish the religious belief in Christ.

3. It is enough merely to answer such things as follows: we are content with the fact that this is not the teaching of the Catholic Church, nor did the fathers hold this. But lest the ‘inventors of evil things Romans 1:30 ‘ make entire silence on our part a pretext for shamelessness, it will be well to mention a few points from Holy Scripture, in case they may even thus be put to shame, and cease from these foul devices.

As we can see it “is enough” for the faith of the Fathers derived from the Scriptures alone (“by itself”) to address all issues of impiety. As I covered elsewhere, Athanasius ascribed to the all-sufficiency of Scripture in matters of doctrine.

Further, “it is enough” to simply say, “No one has ever taught your nutty idea in church history, so I don’t think it merits any consideration.” I have used this argument when addressing the issue of headcoverings. We can easily employ this argument to denounce Gnosticism, the idea that all Jews are saved, Mormonism, and etcetera.

So, my point is this: Irenaeus believes that the Scriptures are the foundation of all necessary doctrines. However, to buoy this point, he also makes the historical argument that Gnosticism is nonsense that has never been recognized by the church. In doing this, Irenaeus is not defending apostolic succession’s role in the validity of sacraments or the existence of an independent tradition that is extra-biblical. Rather, he points to the independent tradition of the church in showing that biblical doctrines, as he understands them, have historical merit.

Let me make my case as briefly as possible:

[I]n this, the third book I shall adduce proofs from the Scriptures, so that I may come behind in nothing of what you have enjoined; yea, that over and above what you reckoned upon, you may receive from me the means of combating and vanquishing those who, in whatever manner, are propagating falsehood (Preface).

So, we know he views the Scriptures as “the means” of combating false doctrine.

…the only true and life-giving faith, which the Church has received from the apostles and imparted to her sons. For the Lord of all gave to His apostles the power of the Gospel (Preface).

True teaching is what is taught by the Apostles and then passed on.

We have learned from none others the plan of our salvation, than from those through whom the Gospel has come down to us, which they did at one time proclaim in public, and, at a later period, by the will of God, handed down to us in the Scriptures, to be the ground and pillar of our faith (Chap 1).

1. The Apostles passed on the Gospel in public (not private as the Gnostics claimed.)

2. The Apostles passed on the same Gospel in writings, which are intended to be the very basis of Christian faith.

These have all declared to us that there is one God, Creator of heaven and earth, announced by the law and the prophets; and one Christ the Son of God. If any one do not agree to these truths, he despises the companions of the Lord (Chap 1).

The Apostolic writings had in common that they all declared the above essential truths. Obviously, the Gnostics rejected all of these and in doing so rejected the Gospel.

When, however, they are confuted from the Scriptures, they turn round and accuse these same Scriptures, as if they were not correct, nor of authority, and [assert] that they are ambiguous, and that the truth cannot be extracted from them by those who are ignorant of tradition. For [they allege] that the truth was not delivered by means of written documents, but vivâ voce (Chap 2).

Being that the Gnostics reject what the Apostolic writings had in common, they reject the Scriptures in several different ways. They either dispute the Canon or claim that the Scriptures are interpreted wrong apart from their own traditions. Further, they postulate that necessary truths exist via oral tradition and not strictly in written documents.

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 (Chap 2).

Here, we can see the reason Irenaeus cites apostolic succession, because it is a way of disputing Gnostic claims to receiving Apostolic doctrines viva voce. Obviously, Irenaeus believes that citing succession proves that the Gnostics do not have any valid extra-biblical oral traditions handed on to them. We can also see this idea in the following:

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 (Chap 3).

Staying on this subject, Irenaeus makes the following point:

1. 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 (Chap 4).

In short, why seek out a supposed tradition that is “secret” when Apostolic Succession, found among the churches universally acknowledged to be started by the Apostles, proves that there is a historically founded tradition for all to see?

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 (Chap 4)?

The preceding passage is so simple, and yet in my previous post I bungled it very badly. Irenaeus asks a rhetorical question to a specific audience: Christians. He says, “Suppose there arise a dispute…among us.” The Gnostics are not part of “us.” He is speaking to Christians.

So, he says, pretend that we had a dispute over a doctrinal matter. We should obviously turn “to the most ancient Churches with which the apostles held constant [written] intercourse and learn from them what is certain.” But, let’s pretend these writings did not exist. It is enough that a disputable doctrine is “not the teaching of the Catholic Church, nor did the fathers hold this” to reject such an idea.

As independent verification of this idea, Irenaeus postulates what would happen if someone took historically unknown Gnostic doctrines and present them to barbarians who are illiterate, but have faithfully preserved what the Apostles have otherwise left us in their writings:

To which course many nations of those barbarians who believe in Christ do assent, having salvation written in their hearts by the Spirit, without paper or ink, and, carefully preserving the ancient tradition, believing in one God, the Creator of heaven and earth, and all things therein, by means of Christ Jesus, the Son of God; who, because of His surpassing love towards His creation, condescended to be born of the virgin, He Himself uniting man through Himself to God, and having suffered under Pontius Pilate, and rising again, and having been received up in splendour, shall come in glory...Those who, in the absence of written documents, have believed this faith, are barbarians, so far as regards our language; but as regards doctrine, manner, and tenor of life, they are, because of faith, very wise indeed…If any one were to preach to these men the inventions of the heretics, speaking to them in their own language, they would at once stop their ears, and flee as far off as possible, not enduring even to listen to the blasphemous address.

We can see two obvious things. First, the barbarians’ general sense of Christian religion without the Scriptures is obviously Scriptural. Second, Gnostic doctrines and extrapolations are completely unknown to them. From both of these things, we may conclude that Irenaeus and other catholics are reading the right Scriptures and arriving at the right interpretations.

Let me try to illustrate this with a real-world example. There is a Korean cult started by Ahn Sahng Hong that teaches there being a perverted Trinity: the Father, the Son, and the Mother. I know the Scriptures. When I ask one of the cultists where on Earth they got this idea from, the cultist replies that 1. It was personally revealed to Ahn Sahng Hong and 2. Gal 4:26 says so (“The Jerusalem above is free and she is our mother.”) Obviously, I can disprove this nonsense from the works of Paul himself.

However, how did my mother-in-law know it was a bunch of crap? She can read Vietnamese, but she only has a Khmer Bible (which she obviously cannot read.) When she hears this Father-Son-Mother stuff, she simply knows from having heard the Bible and doctrinally correct teaching that the stuff is nonsense.

Unlike my mother-in-law, the barbarians never heard the Scriptures read to them.They only heard what their forefathers said the Apostles, who wrote those Scriptures, taught. Yet, the end-result is the same. They are able to realize that these new-fangled doctrines do not match up with what they have heard was authentically Apostolic.

So, if we theoretically had no recourse to writings to settle the doctrinal matter of Gnosticism, the following is enough: that the plain testimony of every single church, which can prove it was actually started by an Apostle in the last 100 years or so, never taught Gnostic doctrines nor shared their interpretations.

The above does not disprove the sufficiency of Scripture or allow us to posit there being a deposit of extra-biblical truth necessary for salvation. Rather, it merely serves as an extra nail in the Gnostic’s coffin. The chief nail is the Bible. The Bible nowhere teaches Gnosticism. But, if the Gnostic wants to be really annoying and dispute the Scriptures, then we can still disprove Gnosticism by simply appealing to history.

Being that this specific historic argument is on the forefront of Irenaeus’ mind, he continues with it after he finishes his rhetorical example of the barbarians:

For, prior to Valentinus, those who follow Valentinus had no existence; nor did those from Marcion exist before Marcion; nor, in short, had any of those malignant-minded people, whom I have above enumerated, any being previous to the initiators and inventors of their perversity (Chap 4).

After having finished his historical arguments (which he began to address the Gnostic objection to the Canon and its obvious interpretation as it pertains to Christology) he returns to the “ground and pillar” of the faith–

Since, therefore, the tradition from the apostles does thus exist in the Church, and is permanent among us, let us revert to the Scriptural proof furnished by those apostles who did also write the Gospel, in which they recorded the doctrine regarding God, pointing out that our Lord Jesus Christ is the truth, John 14:6 and that no lie is in Him (Chap 5).

Conclusion. I feel that I have offered here a cogent explanation of Irenaeus’ whole view of tradition, why he invoked the idea to begin with, what he hoped to address, and how it fits with the idea that the Scriptures are sufficient in of themselves to address matters of doctrines without the existence of an infallible teaching authority.

Addendum. In AH 4.26.2, 5 Irenaeus returns to the same subject when addressing proper Scriptural interpretation. He writes:

Wherefore it is incumbent to obey the presbyters who are in the Church—those who, as I have shown, possess the succession from the apostles; those who, together with the succession of the episcopate, have received the certain gift of truth, according to the good pleasure of the Father…they expound the Scriptures to us without danger, neither blaspheming God, nor dishonouring the patriarchs, nor despising the prophets.

Now, it is obvious why this would be of importance according to what Irenaeus had already told us. To read the Scriptures in such a sense that no one has ever understood them would obviously be wrong, just like my mother-in-law understood that the ideas of the Korean-cultists were obviously wacky.

In Chapter 27, Irenaeus then goes on to teach what one these presbyters taught. Quoting the Scriptures, the content of what is taught focuses on how false teachers are punished and proper Christology. In Chapter 31, Irenaeus then cites the same presbyter as evidence that the two daughters of Lot were an allegory for the churches of the Old and New Covenants, and that Lot in the leading up to the sexual act (by eating and drinking, and then sleeping) was prefiguring Christ.

Now, I am not sure how many people would affirm the presbyter’s teaching in chapter 31 as a correct exegesis of Scripture. This would prove that Irenaeus’ method of interpreting Scripture, by looking at how previous interpreters with succession going back to the Apostles, is not fail-safe. Even Catholics would admit that their own church has changed on huge issues such as the atonement. If they simply followed Irenaeus’ method, they would be forced to accept either the Ransom theory or proto-Penal Subsitution.

However, Irenaeus’ point still stands. The consensus of the fathers going back to the Apostles is a very good method for discerning truth from error. Does it have its limitations? Of course. Thankfully, even 2,000 years later, we do not have to seriously confront the rhetorical situation where we have a matter of dispute with no recourse to the Apostles’ writings.