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Course 12 · Lesson 2.1

Irenaeus against the Gnostics: the rule of faith and apostolic succession

12 minute read

Lessons in this course

Course 12 outline

Module 1: The Apostolic Fathers and the Early Apologists

  1. Who the Apostolic Fathers were: Clement, Ignatius, Polycarp and the Didache
  2. Church order, worship and martyrdom in the second century
  3. Why Christians wrote apologies: charges, persecution and public defense
  4. Justin Martyr, philosophy and the Logos

Module 2: Irenaeus, Tertullian and Origen

  1. Irenaeus against the Gnostics: the rule of faith and apostolic succession
  2. Tertullian and the beginnings of Latin theology
  3. Origen: biblical scholarship, allegory and speculation
  4. Heresy and orthodoxy: the scholarly debate about early diversity

Module 3: Creeds and Councils: Nicaea to Chalcedon

  1. From baptismal confession to creed
  2. Arius, the Council of Nicaea (325) and Athanasius
  3. The Cappadocian Fathers and the Council of Constantinople (381)
  4. Ephesus (431) and Chalcedon (451): one Christ, two natures
  5. The seven councils and how the churches receive them

Module 4: Augustine, Chrysostom and the Desert

  1. Augustine: life, conversion and the Confessions
  2. Augustine on grace, the Pelagian controversy and the City of God
  3. John Chrysostom: preacher, pastor and critic of wealth
  4. The Desert Fathers and Mothers: Anthony, Macarius and Amma Syncletica

Module 5: The Medieval Church and Scholasticism

  1. The medieval setting: monasteries, cathedral schools and universities
  2. Anselm and the method of scholasticism
  3. Thomas Aquinas: life and the structure of the Summa Theologiae
  4. Aquinas on faith, reason, nature and grace
  5. East and West: the growing divide and the schism of 1054

Module 6: The Reformation and the Counter-Reformation

  1. Luther and the question of justification
  2. Zwingli, Calvin and the Reformed tradition
  3. The Radical Reformation and the English Reformation
  4. The Council of Trent and Catholic reform
  5. Catholic, Orthodox and Protestant readings of the Reformation

Module 7: Modern Theology and Tracing a Doctrine

  1. The Enlightenment and its challenges to inherited doctrine
  2. Schleiermacher, liberal theology and Karl Barth
  3. Vatican II, Orthodox renewal and the evangelical and Pentecostal movements
  4. How to trace a doctrine: development, change and corruption

All courses

Program / Course 12: Patristics and Historical Theology / Lesson 2.1

What you will learn

  • Describe who Irenaeus was and what he wrote against.
  • Explain what Gnostic teachers taught in general and why Irenaeus opposed them.
  • Define the rule of faith and apostolic succession and explain how Irenaeus used them.
  • Compare how Catholic, Orthodox and Protestant Christians read Irenaeus on tradition and Scripture.

The big idea

Irenaeus, bishop of Lyons in the late second century, wrote the first large Christian work that answers false teaching point by point. He argued that the God who made the world is the Father of Jesus Christ, that matter is good, and that salvation is for the whole person. To show where true teaching is found, he pointed to the Scriptures, the rule of faith held in the churches, and the public succession of bishops from the apostles. Every major Christian tradition draws on Irenaeus, though they read him differently.

Key terms

Gnosticism
A name for several movements of the second century and after that taught that salvation comes through secret knowledge (Greek gnosis). Many held that the material world was made by a lesser or flawed being and that spirit was good and matter bad.
Demiurge
In many Gnostic systems, the lesser creator of the material world, often identified with the God of the Old Testament.
Rule of faith (regula fidei)
A short summary of the central Christian teaching about God, creation, Christ, the Spirit and the last things, passed on in the churches and used as a guide to reading Scripture.
Apostolic succession
The idea that the teaching of the apostles is preserved by an unbroken line of bishops in the churches they founded.
Recapitulation
Irenaeus’s idea that Christ sums up and renews the whole human story, undoing Adam’s disobedience by his own obedience.
Heresy
From a Greek word for choice or party. In church usage, a teaching judged to contradict the faith received from the apostles.
Canon
The list of books the church receives as Scripture.

Background

Irenaeus came from Asia Minor and, by his own report, had heard Polycarp of Smyrna as a boy. He later went to Gaul and became bishop of Lyons about the year 177, after a wave of persecution in which the previous bishop, Pothinus, died. His major work is usually called Against Heresies. Its full title in Greek is closer to Refutation and Overthrow of Knowledge Falsely So Called. It survives mostly in a Latin translation, with parts in Greek and other languages.

The teachers he opposed were various. Valentinus and his followers taught an elaborate story of divine beings and a fall within the divine realm, and described the material world as the product of ignorance. For a long time, these teachers were known mainly through hostile descriptions. In 1945, a collection of Gnostic and related texts was found near Nag Hammadi in Egypt, and it allows historians to read the teachers in their own words. Scholars now agree that the movement was diverse, and they debate how best to define it.

Irenaeus is also a source of positive teaching. He wrote not only to refute but to present a coherent picture of salvation: one God, one Christ and one story from creation to renewal.

Step-by-step explanation

Step 1: What the Gnostic teachers said

Though they differed, many Gnostic teachers shared some features. They claimed a secret knowledge handed down from the apostles, available only to the few. They held that the visible world was a lower or flawed creation, and that the God of the Old Testament was either a lesser being or not the true God. Some taught that Christ only seemed to have a body. Salvation meant escaping from matter, not renewing it.

Gnostic teachers also read Scripture, but selectively and allegorically. Irenaeus compared their method to rearranging the tiles of a mosaic of a king so as to form the picture of a fox.

Step 2: One God, good creation

Against this, Irenaeus insisted that there is one God, who made all things freely and well, and that the same God spoke in the law and the prophets and in the Gospel. The body and the material world are not a mistake. They are the creation of a good God, and God will redeem them.

This is why Irenaeus emphasizes the incarnation. The Word really became flesh. In the preface to his last book, he says that Christ became what human beings are in order to make them what he is. Orthodox Christians often cite this line when explaining theosis, or deification, and other traditions read it differently.

Step 3: The rule of faith

To show what the church teaches, Irenaeus summarizes it. The church, he says, believes in one God, the Father Almighty, who made heaven and earth and the sea and all that is in them; in one Christ Jesus, the Son of God, who became incarnate for human salvation; and in the Holy Spirit, who through the prophets announced the plan of salvation. This summary is not exactly a creed, since it varies in wording, but it is a short form of the same faith.

For Irenaeus, the rule of faith is not a second source added to Scripture. It is the outline of the story that Scripture tells, and it guides how the story is read. Without it, a reader might arrange the verses into a different picture.

Step 4: Apostolic succession

Irenaeus argued that the apostles taught publicly, and that the churches they founded kept what they taught. Anyone who wanted to know the apostolic teaching could look at the churches that could trace their bishops back to the apostles. He gives the example of Rome, listing its bishops from the apostles Peter and Paul down to his own day. If the apostles had secret teaching, he reasoned, they would have given it to those they trusted with their churches, and those people would not have hidden it.

Notice that the argument is about the agreement of many churches, not the power of one office. Irenaeus also says that all churches should agree with Rome because of its pre-eminent origin. The exact meaning of that sentence, which survives in Latin, is debated.

Step 5: The Gospels and the Scriptures

Irenaeus is also an early witness to the four Gospels. He argues that there are four, no more and no fewer, and gives symbolic reasons that most modern readers find unconvincing, such as the four winds and the four corners of the earth. The more important point is that by his time, Matthew, Mark, Luke and John were widely received, while other so-called gospels were rejected. Scholars debate how settled the canon was, but Irenaeus shows a firm core.

  1. Why does it matter to Irenaeus that the Creator is the Father of Jesus?
  2. What is the difference between a secret teaching and a public tradition?
  3. How does a summary of the faith help in reading the Bible?
  4. What is strong and what is weak in the argument from lists of bishops?
  5. Why did Irenaeus insist that Christ really had a body?
  6. Do you think the Gnostic texts should be read by Christians today? Why or why not?

Examples

The mosaic of a king

Irenaeus imagines a skilled artist who makes a mosaic of a king. Someone takes the pieces apart and rearranges them to make a fox. The pieces are real, but the picture is false. He says this is how his opponents treat Scripture.

A visitor in a new city

A traveler arrives in a city and wants to know what the church there believes. Irenaeus thinks the traveler could ask the bishop and compare the answer with what is believed in other cities founded by apostles. Agreement across distant churches is a sign of a common source.

A text from Nag Hammadi

A reader today can open a translation of the Gospel of Truth or the Gospel of Thomas and compare it with Irenaeus’s description. This allows a student to see where Irenaeus summarized fairly and where he may have been unfair.

Different perspectives

Catholic

The Catholic Church cites Irenaeus as a key witness to apostolic succession and to the authority of the bishops in communion with Rome. Catholic teaching holds that Scripture, tradition and the teaching office are bound together, and sees Irenaeus’s argument as an early form of that view.

Orthodox

Orthodox Christians honor Irenaeus as a saint and stress his emphasis on the incarnation and the renewal of creation. They also see in his account of the churches a picture of unity among local churches founded by apostles, without a single supreme bishop.

Protestant

Protestants often point to Irenaeus’s constant appeal to Scripture as the standard, and to his argument that the apostles’ teaching was written down. Many read the rule of faith as a summary of Scripture, not an independent authority. Others, including Anglicans, give more weight to the continuity of the church’s ministry. Protestants disagree about how far the argument supports apostolic succession of bishops.

Scholarly views

Historians note that Irenaeus is an invaluable source but not a neutral one. They compare his account with the Nag Hammadi texts, and they debate how coherent Gnosticism was as a category. Some scholars argue that the later boundary between orthodoxy and heresy was drawn more clearly than in his day, a question taken up in a later lesson.

Why it matters

Irenaeus asked a question that every generation faces: how can anyone know what the apostles really taught? His answer combined Scripture, the faith summarized in the churches and the public continuity of teaching. Christians still disagree about how those three fit together, so studying him is a way to see the starting point of those disagreements.

Common misunderstandings

Misunderstanding: Irenaeus invented the idea of orthodoxy to crush his opponents.

Correction: Irenaeus was defending what he believed to be the received teaching of the churches. Whether he described his opponents fairly is a separate question that scholars study by comparing his account with the Nag Hammadi texts.

Misunderstanding: The rule of faith is the same as the Apostles’ Creed.

Correction: They are related but not identical. The rule of faith varies in wording from writer to writer, while the creeds are fixed texts that developed later.

Misunderstanding: Apostolic succession means every bishop is automatically correct.

Correction: Irenaeus uses succession as a sign of public continuity of teaching. He ties it to the teaching itself. How strictly a church links succession and doctrinal reliability varies by tradition.

Misunderstanding: All Gnostics believed the same thing.

Correction: The teachers differed widely. Scholars use the word Gnosticism as a convenient label and argue about whether it is too broad.

Knowledge check

Who was Irenaeus, and what did he write?

Irenaeus was bishop of Lyons in Gaul from about 177. He had heard Polycarp of Smyrna as a young man. His major work, Against Heresies, refutes Gnostic teachers and sets out a positive account of the faith. It survives mostly in Latin translation, with parts in Greek.

What is the rule of faith?

It is a short summary of the central teaching about the one God, the Father who made all things, Jesus Christ the Son who became flesh for salvation, and the Spirit who spoke through the prophets. Irenaeus treats it as the outline of the story Scripture tells and a guide to reading it.

How did Irenaeus use apostolic succession?

He argued that the apostles’ public teaching was kept in the churches they founded, and that the lists of bishops from the apostles show a continuous line. A secret teaching, he said, would have been handed to those leaders. He used Rome as a clear example and also appealed to the agreement of many churches.

Why did the discovery at Nag Hammadi matter?

In 1945 a collection of Gnostic and related texts was found in Egypt. Before that, historians knew Gnostic teachers mostly through hostile accounts such as Irenaeus’s. The texts let scholars read the teachers in their own words, check how fairly they were described, and see that the movement was diverse.

Think it through

  1. When you read a hard passage, what do you bring to it from your church or family that shapes how you read it?
  2. Is a public tradition more trustworthy than a private insight? What are the limits of each?
  3. What do you think of Irenaeus’s claim that the material world is good and will be redeemed?
  4. How would you tell a fair summary of an opponent from an unfair one?

Independent assignment

The rule of faith in your own words

Read Against Heresies, Book 1, chapter 10, on the faith received by the church, and Book 3, chapters 1 to 4. In your notebook, copy out the rule of faith in a form of about 100 words in your own words. Then write two paragraphs: one on how it helps read Scripture, and one on a way Irenaeus’s approach could be abused or misunderstood. Aim for 400 to 600 words.

Further study