In his recent article, “Why do our Bibles contain these books and not others?” Tony Watkins provides an overview of how the Bible’s 66 books came to be included within its covers. We can be confident that these are the books God wanted to be preserved through the ages.
The most important thing to grasp is the fundamental reason why these 66 books became the canon. It is not because the early Christians particularly liked these books. And it’s not because they were widely accepted, or because some church council decided to make them authoritative. Rather, it is because the early church recognised that these books had an inherent authority for how Christians live and what they believe. They believed that these books would have that same authority through all generations.