Claims Examined · Church History
The Council of Nicaea decided which books belong in the Bible.
Our rating
Not supportedHigh confidenceIn brief
No surviving record of the council discusses the biblical canon. In AD 325 the bishops met to answer Arius, who taught that the Son was a created being. They confessed the Son to be “of one substance” with the Father, and they also set the date of Easter and issued twenty canons on church order.
Where this claim comes from
Repeated in popular books such as The Da Vinci Code, in films and on social media.
Weighing the evidence
Supports the claim
- None from the council’s records or from contemporary accounts.
Counts against it
- The Nicene Creed and the twenty canons say nothing about which books are Scripture.
- Eusebius, who attended, describes the proceedings without mentioning the canon.
- The first list matching our 27-book New Testament exactly is Athanasius’ Festal Letter of AD 367, decades later.
- Churches were already reading the Gospels and Paul’s letters as Scripture long before 325.
Discussion
The myth gets Nicaea wrong in a way that hides why the council actually mattered. The bishops were not choosing books. They were answering a question about who Jesus is.
What the council was about
Arius, a presbyter in Alexandria, taught that the Son was the first and greatest thing God created, so that “there was when he was not.” That struck at the heart of Christian worship. If the Son is a creature, praying to him is idolatry. The bishops gathered at Nicaea in AD 325, at the emperor Constantine’s invitation, to settle it.1
What they decided
The council confessed that the Son is “true God from true God, begotten, not made, of one substance with the Father.” They grounded this in texts such as , where the Word is God and all things were made through him. They also agreed on how to calculate Easter and issued twenty canons on church order.2
What they didn’t do
None of the council’s documents, and none of the eyewitness accounts, discuss which books belong in the Bible. The New Testament took shape gradually through use in the churches. The first list matching our 27 books exactly comes from Athanasius in AD 367, more than forty years after Nicaea.3
Read the long read: What the Council of Nicaea actually decided — and what it didn’t →
Sources reviewed
- primaryEusebius of Caesarea, Life of Constantine. Book III.
- secondaryLewis Ayres, Nicaea and Its Legacy. Oxford University Press, 2004.
- secondaryBruce M. Metzger, The Canon of the New Testament. Oxford University Press, 1987.
- primaryAthanasius of Alexandria, Festal Letter 39. AD 367.
Review history
- First published.