That is a critically important question, since there are many today who would deny that these 66 books truly make up the complete canon of Scripture.
The Roman Catholic Church, for example, claims that the Apocryphal books which were written during the inter-testamental period (between the Old and New Testaments) ought to be included in the Bible. Cult groups like the Mormons want to add their own books to the Bible—like the Book of Mormon, The Doctrines and Covenants, and The Pearl of Great Price. And then there are popular books and movies, like The Da Vinci Code, that claim centuries after these books were written Christians (like Constantine) determined what was in the Bible.
So, how do we know that “all Scripture” consists of these 66 books? How do we know that the Bible we hold in our hands is the complete Word of God?
There are a number of ways we could answer such questions; in fact, we could spend weeks studying the doctrine of canonicity, carefully walking through the relevant biblical and historical details. And there are many helpful books that can guide you through that wealth of information.
But in this article, I would like to offer a simple answer that I hope will be helpful – because it gets to the heart of the matter.
It is this: We believe in the 39 books of the Old Testament, because the Lord Jesus Christ affirmed the Old Testament. And we believe in the 27 books of the New Testament, because the Lord Jesus Christ authorized His apostles to write the New Testament.
The doctrine of canonicity is grounded in the lordship of Jesus Christ. If we believe in Him and submit to His authority, then we will simultaneously believe in and submit to His Word. Because Jesus affirmed the Old Testament canon, we affirm it with Him. Because He authorized His apostles to write the New Testament, we also embrace it.
