It was inevitable that Christianity would become a religion with a sacred book. Inheriting a collection of texts from their parent religion, Judaism, early believers in Jesus not only read Israel’s ancient books differently than their fellow Jews who did not believe Jesus to be the Messiah, they also began to develop their own set of texts, some of which would eventually become the New Testament. This was an historical process that involved human decisions that would define the Christian Bible.
Over the period of time between the life of Jesus and what I would cautiously refer to as the “closing” of the New Testament canon, texts were written, copied, and passed from church to church. Because of the flux intrinsic to such an historical process, we cannot say with any degree of certainty that what would eventually become known as the New Testament was known by these early Christians. Indeed, for centuries there was no such thing as a New Testament in the shape we know it today.
What was the historical process that led to 27 books becoming the New Testament? Step one of this progression was the writing of texts in response to what early followers of Jesus believed about him. This does not mean complete uniformity, for as Christianity grew, different Christian communities developed different understandings about who Jesus was, and they wrote texts that reflected their views.
A vitally important step to follow was the reading of texts in worship. We know that Paul’s letters were being read in the congregations to which he had written. Moreover, the Gospels give evidence that they were addressed to particular Christian communities, which would mean that they were read in these churches. This public reading of these texts caused them to be viewed as authoritative scripture, which led not only to the copying of these texts, but also to their dispersal to various Christian communities.
Public reading and the sharing of writings with other churches also led to some books becoming authoritative for some churches, while other books would not be viewed as scripture by these churches. As Christianity spread away from Jerusalem, Christian texts became more diverse, so much so that it would have been impossible for wide-ranging agreement on the Christian canon to take place across the vastness of the Roman Empire.
Indeed, there were books, such as Hebrews and 2 Peter, which were not necessarily viewed as scripture by many churches which would become part of the New Testament. There were also other writings, such as 1 and 2 Clement and the Shepherd of Hermes, that were viewed as scripture by many churches, and yet they would not be included in the books of the Christian Bible.
Therefore, we have little evidence that a universal New Testament existed before the fourth century. Rather, various Christian communities held their own canons as authoritative. But for many church authorities, this kind of pluralism would not do, and they sought to bolster what they determined as orthodox.
While there were always those on the fringe of this orthodoxy, the popularity of the teachings of a man named Marcion (85-160 C.E) presented a significant threat to the church authorities. Marcion excluded the Hebrew Bible or Old Testament and included in his scriptures only ten letters of Paul and a particular version of Luke, free of any references to Jesus’ Jewish heritage.
Marcion’s influence was significant enough to gather a large following and the attention of church authorities. The popularity of his teachings, even long after his death, as well as the beliefs of other unorthodox communities, convinced church leaders that a defined canon of scripture needed to be finalized. This would be the only way to root out potential challenges to what church authorities considered orthodoxy.
But it was not until 367 C.E. that a list of the 27 books was affirmed as the canon of the New Testament. The canonical list appears in a letter written by a bishop named Athanasius and excludes those books considered heretical by the church, as well as some books that were popular even among orthodox Christians. By the time of this letter, the Council at Nicaea (325 C.E.), which was called and influenced by Emperor Constantine, had already decided what orthodoxy was, and thus teachings outside of their definition would be deemed heretical.
Why should all of this matter to modern Christians who have lived all of their lives with a complete New Testament? Primarily, this historical process demonstrates that as Christianity developed some Christian groups, in response to what they believed about God and in reaction to opposing views from other Christian groups, made decisions about what would be called the New Testament.
More importantly for shaping theology today, looking back on this process raises certain questions about the range of the canon of scripture, about who determines what the Bible is and says, and to what extent the scriptures serve as the sole basis of authority for Christian faith and living.