How the Canon Was Formed

The most common dismissal of the New Testament's authority runs something like this: "The Bible was put together by a council of men at Nicaea in 325 who voted on which books to include and which to suppress, based on political considerations." This version of events is widely believed and almost entirely wrong. The Council of Nicaea, which met to settle the Arian controversy about the nature of Christ, did not produce a canon of Scripture; the bishops who attended it brought their own copies of what were already recognized as the Scriptures. The 27 books of the New Testament were not voted into existence by any single council. They were recognized — gradually, by multiple independent communities, using consistent criteria, arriving at the same result — across roughly three centuries. This page traces that process honestly, including the books that were debated late and the reasons they were debated.

What the New Testament claims about itself

Before tracing the historical process, it is worth noting that the New Testament documents themselves show an early awareness that some writings carried a different authority than others. Peter, writing his second letter, groups Paul's letters with "the other scriptures" and mentions that the untaught "wrest" them to their own destruction — treating Paul's letters as Scripture before any council had declared them such (2 Peter 3:16). Paul, writing to Timothy, applies the phrase "God-breathed" (theopneustos) to Scripture, and his letter itself is the kind of document that would later be recognized under that category (2 Timothy 3:16). The letters were being copied and circulated among churches from the beginning (Colossians 4:16); the question of which ones carried apostolic authority was live from the first generation.

The three criteria the early church applied

The churches did not select books arbitrarily. Three consistent tests appear across the patristic writings:

Apostolicity. Did the book originate with an apostle or a close associate of one? The four Gospels were accepted early in part because their connection to eyewitnesses was documented and widely affirmed. Mark was understood to represent Peter's preaching; Luke was Paul's traveling companion and wrote under his influence. John, Matthew, and Paul's letters were accepted as directly apostolic. This criterion is why some books were debated longer: Hebrews had no clear author named in the text, and Revelation was attributed to John but with questions about which John.

Catholicity. Was the book used widely and consistently across the churches? A book that circulated in one region but was unknown in others raised questions. A book recognized independently from Rome to Alexandria to Antioch to Carthage had strong evidence of authenticity. The letters of Paul, by the early second century, were already being collected and read across the Greek-speaking world. The four Gospels were in use everywhere long before any formal list.

Orthodoxy. Did the teaching of the book align with what the apostles had handed on? This is what Irenaeus and Tertullian called the "rule of faith" — the core apostolic content that could be recited from memory and that every true church shared, independent of any text. A book that claimed apostolic authorship but taught something incompatible with that rule was suspect. This is the criterion that ruled out books like the Gospel of Thomas (gnostic content) and the Gospel of Peter (a docetic Christ who felt no pain at the crucifixion).

The first generation: Paul's letters and the Gospels

By the early second century, the core of the New Testament was already functioning as Scripture in the churches. Clement of Rome (writing around AD 96) quotes from Matthew, Luke, Romans, 1 Corinthians, and Hebrews. Ignatius of Antioch (writing around AD 110, on his way to martyrdom in Rome) quotes or alludes to Matthew, John, Romans, 1 and 2 Corinthians, Galatians, Ephesians, Colossians, and 1 Timothy. Polycarp (writing to the Philippians around AD 115) quotes from Paul's letters across at least eight books. None of these writers are proposing a canon; they are treating what they already regard as Scripture.

The Muratorian Fragment (c. AD 170–200), one of the earliest canonical lists to survive, includes: four Gospels, Acts, Paul's letters (thirteen of them), 1 and 2 John, Jude, and Revelation. It explicitly excludes the Shepherd of Hermas from the canon while acknowledging its value for private reading. It excludes letters circulating under Paul's name that were known to be forgeries. The criteria are applied explicitly in the text itself.

The books that were debated

Honesty requires acknowledging that several of the 27 were disputed for longer than others. This is not a scandal; it is evidence that the church was applying its criteria carefully rather than accepting everything presented to it.

Hebrews — accepted as Scripture throughout the East, whose tradition attributed it to Paul; debated longer in the West, where the authorship question was more openly acknowledged. Origen (c. 248) wrote: "Who wrote the epistle, in truth God knows." The Eastern church's acceptance was enough to carry it into the final consensus.

James — accepted in the East but debated in some quarters over its relationship to Paul's teaching on faith and works. The letter itself has an unusually Jewish character and does not refer explicitly to the resurrection. It entered the final canon without controversy by the late fourth century.

2 Peter — the most debated of the letters. Its Greek style differs significantly from 1 Peter, and Eusebius (c. 313) placed it among the "disputed" books, though he noted it was acknowledged by most. It entered the canon as 2 Peter, widely accepted by the late fourth century.

2 and 3 John and Jude — short letters with limited circulation in some regions, debated mainly on that basis rather than on doctrinal grounds.

Revelation — accepted in the West from early on; disputed longer in the East, where some churches read it and some did not, partly over authorship questions and partly over interpretive concerns about apocalyptic excess. By the late fourth century it was in the consensus list, though it remained disputed in some Eastern traditions longer than the others.

Athanasius and the year 367

In his Easter Letter of AD 367 — the annual letter Alexandria's bishop sent to the churches in Egypt setting the date of Easter and addressing pastoral matters — Athanasius included a list of the books that were to be read as Scripture. It is the earliest surviving document to list exactly the 27 books of the New Testament that Protestants, Catholics, and Eastern Orthodox all agree on today, in those words, with no additions or subtractions. He wrote: "These are the wells of salvation, so that he who thirsts may be satisfied with the sayings in these. Let no one add to these or take away from these." He was describing what the churches of his tradition already used, not legislating a new list — but the document is a landmark because it shows that by 367 the consensus had crystallized to exactly 27.

The councils that formally ratified the 27-book canon — the Council of Hippo (393) and the Third Council of Carthage (397), both in North Africa — did not create the canon. They recognized what the churches had already been using for generations. This is the pattern throughout: the councils followed the churches; the churches had followed the apostles; the apostles had followed the Lord.

The Nicaea myth, addressed directly

The Council of Nicaea (325) dealt with one question: was Christ of the same substance as the Father, or a created being who came first among created beings? The bishops answered with the word homoousios — of the same substance — and produced the Nicene Creed. The canon of Scripture was not on the agenda, did not appear in the council's decisions, and is not mentioned in any contemporary account of the proceedings. The myth that Nicaea voted on the canon appears to have no traceable historical basis before the twentieth century. It is sometimes associated with books like Dan Brown's The Da Vinci Code (fiction presented as historical fact), but in the historical record of the actual council it is simply absent.

Why the 27 are the 27

The result of three centuries of consistent recognition across geographically separated communities, applying the same three criteria, is the 27 books. The books that were eventually excluded — the Gospel of Thomas, the Shepherd of Hermas, the Didache, the Epistle of Barnabas — were excluded for identifiable reasons applied consistently: late authorship, doctrinal incompatibility with the rule of faith, or limited and regional use. Several of these books are valuable historical documents, which is why they appear in this site's beyond-canon section; none of them met the criteria for inclusion in the New Testament itself.

The honest case for the canon is not that it was infallibly assembled by infallible men in a single meeting. It is that the churches, independently across the ancient world, under no single centralized authority, arrived at the same 27 — and that this convergence is itself evidence that what they were recognizing was recognizable: books that carried the apostolic content, the apostolic authority, and the life-giving character Paul described as God-breathed. The Spirit the church believed had inspired the documents also appears to have guided their recognition.

Related: The Authority of Scripture, Athanasius (whose Easter Letter of 367 is the first to list exactly our 27), What the Early Church Confessed, Beyond the Canon (the deuterocanon and other early writings). Sources: the Muratorian Fragment (c. AD 170–200); Eusebius, Church History (public-domain, NPNF); Athanasius, Festal Letter 39 (public-domain, NPNF); F.F. Bruce, The Canon of Scripture (IVP, 1988) for historical context.