Canonicity
HOW DO WE KNOW WHICH BOOKS BELONG IN THE BIBLE? The Question of Canonicity
We have certainty about the canonicity of the books in the Old Testament, which Jesus referred to as “all the Scriptures”, and those in the New Testament. Three crucial passages from the Bible itself indicate that books of the New Testament were already considered Scripture before the New Testament was even completed. Books of the New Testament were recognized as Scripture immediately upon publication because apostles themselves designated these books as Scripture.