canon means a "rod" - specifically, a rod with graduated marks used
for measuring length. This word refers to the list of individual
books that were eventually judged as authoritative and included as a
part of the Old Testament and the New Testament.
The early formation of the canon of the Old Testament is not easy to trace. Its threefold division in its early history - the Law, the Prophets, and the Writings - may reflect the three stages of its formation. From the beginning, the Law was accepted, even if it was not always obeyed. Evidence of its acceptance would include Moses' reading of "the Book of the Covenant" to the people at Mt. Sinai and the people's response, "All that the LORD has said we will do, and be obedient" (Exod. 24:7).
Further evidence of acceptance of the Law includes the discovery of the "Book of the Law", probably the Book of Deuteronomy, in the Temple of Jerusalem during King Josiah's reign and the religious reform which followed (II Kings 22:8-23:25). Also, following the return of the Jewish people from the Babylonian Captivity, "the Book of the Law of Moses" was read to the people of Jerusalem under Ezra's direction. This book became the constitution of their new nation (Neh. 8:1-18).
The second division of the Old Testament accepted by the Jewish people was the Prophets. The prophets' words were preserved from the beginning by their disciples, or by others who recognized the prophets as messengers of GOD. In general, their words were probably written shortly after they were spoken, for their authority as GOD's messengers came before their widespread acceptance by the Jewish people. The words of the prophets were not regarded as authoritative because they were included in the Old Testament; they were included because they were considered to be authoritative.
The third division of the Hebrew Old Testament, the Writings, may have remained "open" longer than the first two. Scholars know less about the formation of this division than the first two.
The "Bible" which Jesus used was the Hebrew Old Testament. He left no instructions about forming a new collection of authoritative writings to stand beside the books which He and His disciples accepted as GOD's Word. The Old Testament was also the Bible of the early church, but it was the Old Testament as fulfilled by Jesus. Early Christians interpreted the Old Testament in the light of His person and work. This new perspective controlled the early church's interpretation to such a degre that, while Jews and Christians shared the same Bible, they understood it so differently that they might almost have been using two different Bibles.
The works and words of Jesus were first communicated in spoken form. The apostles and their associates proclaimed the gospel by word of mouth. Paul taught the believers orally in the churches which he founded when he was present. But when he was absent, he communicated through his letters.
Quite early in its history, the church felt a need for a written account of the teachings of Jesus. His teachings did provide the basis for the new Christian way of life. But the church grew so large that many converts were unable to rely on the instructions of those who had heard and memorized the teachings of Jesus. From about A.D. 50 onward, probably more than one written collection of sayings of Jesus circulated in the churches. The earliest written gospel appears to have been the Gospel of Mark, written about A.D. 64.
An individual gospel, a letter from an apostle, or even several works circulating independently, would not amount to a canon, or an authoritative list of books. A canon implies a collection of writings. There is evidence that two collections of Christian writings circulated among the churches at the beginning of the second century. One of these was the gospel collection - the four writings which are commonly called the four gospels. The other collection was the Pauline collection, or the letters of the apostle Paul. The anonymous letter to the Hebrews was added to this second collection at an early date.
Early Christians continued to accept the Old Testament as authoritative. But they could interpret the Old Testament in the light of Jesus' deeds and words only if they had a reliable record of them. So, alongside Moses and the prophets, they had these early writings about Jesus and letters from the apostles, who had known Jesus in the flesh.
When officials of the early church sought to make a list of books about Jesus and the early church which they considered authoritative, they retained the Old Testament, on the authority of Jesus and His apostles. Along with these books they recognized as authoritative the writings of the new age - four gospels, or biographies on the life and ministry of Jesus; the 13 letters of Paul; and letters of other apostles and their companions. The gospel collection and the apostolic collection were joined together by the Book of Acts, which served as a sequel to the gospel story, as well as a narrative background for the earlier epistles.
The primary standard applied to a book was that it must be written either by an apostle or by someone close to the apostles. This guaranteed that the writing about Jesus and the early church would have the authenticity of an eyewitness account. As in the earliest phase of the church's existence, "the apostles' doctrine" (Acts 2:42) was the basis of its life and thought. The apostolic writings formed the charter, or foundation documents, of the church.
None of the books written after the death of the the apostles were included in the New Testament, although early church officials recognized they did have some value as inspirational documents. The fact they they were written later ruled them out for consideration among the church's foundation documents. These other writings might be suitable for reading aloud in church because of their edifying character, but only the apostolic writings carried ultimate authority. They alone could be used as the basis of the church's belief and practice.
Behind the Bible is a thrilling story of how GOD revealed Himself and His will to human spokesmen and then acted throughout history to preserve His Word and pass it along to future generations. In the words of the prophet Isaiah, "The grass withers, the flower fades, but the word of our GOD stands forever" (Isaiah 40:8).
Taken from: the "Illustrated Dictionary of the Bible" by Herbert Lockyer, Sr., Editor with F. F. Bruce and R. K. Harrison, published by Thomas Nelson Publishers in 1986.