Is the Bible the only rule of faith, or is church tradition also binding?

Irenaeus of Lyons c. 130–c. 202 ADAgainst Heresies 3.4.1

What if the apostles had not even left us Scriptures? Would we not have had to follow the order of the tradition they handed on to those to whom they entrusted the churches? Many barbarian peoples who believe in Christ assent to this order. They have salvation written in their hearts by the Spirit without paper or ink, and carefully keep the ancient tradition, believing in one God, maker of heaven and earth and all that is in them, through Christ Jesus the Son of God.

Irenaeus is not setting tradition against Scripture; he has just spent two books arguing from Scripture. His point is that the apostles' teaching was also kept alive in the churches they founded.

Tertullian c. 155–c. 220 ADPrescription against Heretics 19

So we must not appeal to the Scriptures, nor fight the battle on ground where victory is impossible, or uncertain, or barely certain. ... The question to settle first is this: to whom does the faith itself belong? Whose are the Scriptures? From whom, through whom, when and to whom was the teaching handed down by which people become Christians? For where the true Christian teaching and faith are shown to be, there will be the true Scriptures, the true interpretations, and all the true Christian traditions.

Tertullian's legal argument: heretics have no title to Scripture, because it belongs to the churches the apostles founded. In other books he argues from Scripture at length.

Athanasius of Alexandria c. 293/298–373 ADAgainst the Heathen 1.3

The holy and God-breathed Scriptures are sufficient for the proclamation of the truth. There are also many works composed by our blessed teachers on these matters; whoever reads them will learn something of the interpretation of the Scriptures.

Both sides of the later debate quote this sentence: the first half for Scripture's sufficiency, the second for the help of the Church's teachers in reading it.

Cyril of Jerusalem c. 313–386 ADCatechetical Lectures 4.17

Concerning the divine and holy mysteries of the faith, not even the smallest point should be handed on without the divine Scriptures, nor should we be carried away by mere plausible arguments and clever words. Do not simply believe me when I tell you these things, unless you receive the proof of what I announce from the divine Scriptures. For the saving power of our faith comes not from clever reasoning but from proof out of the divine Scriptures.

Said to candidates for baptism while handing them the creed. The same lectures also pass on unwritten customs of the rite.

Basil of Caesarea c. 330–379 ADOn the Holy Spirit 27.66

Of the doctrines and proclamations kept in the Church, some we have from written teaching, and others we have received handed down to us in a mystery from the tradition of the apostles. Both have the same force for true religion. No one will dispute this, at least no one with even a little experience of church practice.

Basil's examples are practices: signing with the cross, facing east to pray, the words of the Eucharistic prayer, threefold immersion. He uses them to defend a form of praise to the Holy Spirit.

Epiphanius of Salamis c. 310/320–403 ADPanarion (Medicine Chest against Heresies) 61.6.4–5

One must use tradition too, for not everything can be taken from the divine Scripture. That is why the holy apostles handed some things down in writings and others in traditions, as the holy apostle says: "as I handed on to you" (1 Corinthians 11:2), and elsewhere: "so I teach, and so I have handed on in the churches".

Written against a group that forbade marriage after vowed virginity. Epiphanius's examples are church rules of practice.

Gregory of Nyssa c. 335–c. 395 ADOn the Soul and the Resurrection library section 12

We have no share in that freedom, I mean to say whatever we like. We use the Holy Scripture as the rule and law of every doctrine. We must look to it, and accept only what agrees with the intent of what is written.

Gregory contrasts Christian teachers with the philosophers, who reason freely about the soul.

Augustine of Hippo 354–430 ADOn Christian Teaching 2.9.14

In what is plainly set down in the Scriptures are found all the things that make up faith and the way of life, that is, hope and love.

Augustine also teaches that the Church's authority moves people to believe the Gospel, and he defends customs held everywhere as apostolic though unwritten (On Baptism 4.24.31).

Augustine of Hippo 354–430 ADAgainst the Letter of Mani called Fundamental 5.6

For my part, I would not believe the Gospel unless the authority of the Catholic Church moved me.

Augustine turns the Manichaeans' own appeal to the Gospel back on them: he believed the Gospel on the preaching of the Catholic Church, so the authority that commended the Gospel to him is the same authority that tells him not to believe Mani. He asks why he should obey the Catholics when they say 'believe the Gospel' but not when they say 'do not believe the Manichaeans'. The locked library text spells the verb conmoueret.

John Chrysostom c. 349–407 ADHomilies on 2 Thessalonians 4.2

"So then, brothers, stand firm and hold the traditions you were taught, whether by word or by our letter" (2 Thessalonians 2:15). From this it is clear that they did not hand down everything by letter, but many things also without writing, and these are just as worthy of trust. So let us count the tradition of the Church worthy of belief too. It is a tradition: seek nothing further.

Preached at Constantinople. Chrysostom elsewhere urges his people to read the Scriptures at home and calls ignorance of them the cause of all evils.

Vincent of LérinsCommonitorium 2.4–5

The canon of Scripture in itself fully and more than suffices for all things: why then must the authority of the Church's understanding be joined to it? Because plainly, on account of its very depth, not everyone takes sacred Scripture in one and the same sense, but one person interprets its words in one way and another in another, so that it seems almost as many opinions can be drawn out of it as there are people. ... Because of the great windings of error in its many forms, it is very necessary that the line of prophetic and apostolic interpretation be directed by the rule of the Church's catholic sense.

Vincent grants the objector's premise: the canon of Scripture is perfect (perfectus) and sufficient in itself. His point is about reading it. Because of its depth, Novatian, Sabellius, Donatus, Arius and the rest all expound it differently, so its interpretation must be ruled by the catholic sense of the Church, the test he states next: what has been believed everywhere, always and by all (2.6).

Council of Trent (Catholic)Session 4 Decree on the Canonical Scriptures

...the 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 ... receives and venerates with an equal affection of piety, and reverence, all the books both of the Old and of the New Testament ... as also the said traditions

Trent's answer to the Reformers. Catholic teaching since Vatican II (Dei Verbum 9) speaks of Scripture and tradition as one deposit flowing from one source.

Ludwig Crocius (Reformed) 1586–1655 ADSyntagma of Sacred Theology 1, chapter 6

So much for the perfection and sufficiency of Holy Scripture. Next comes its clarity: the property by which all the things that make up faith and the way of life are so plainly set down and found in it that, with due care and prudence and suitable means, by God's help, those who fear God and claim nothing for themselves or their own judgment can know them with certainty, each according to his age, and understand them for salvation.

A Reformed professor at Bremen builds his definition of Scripture's clarity on Augustine's sentence (On Christian Teaching 2.9.14).

Westminster Confession (Reformed)Westminster Confession of Faith 1.6

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 new revelations of the Spirit, or traditions of men.

The Reformed statement of Scripture's sufficiency. Lutherans say the same in the Formula of Concord (1577): Scripture is "the only rule and norm".