Sixty six books, forty or more authors, written over thousands of years, written on three continents, in three different languages, by people from diverse walks of life. Normally, if we had such a collection of books and authors, how likely would it be that they would agree on controversial topics? Topics such as the nature of God, what is right and wrong, how one is made right with God, etc.
It would be hard to get agreement on these topics even in one time period, one language, one profession, or even one church!
Yet in the Bible we have consistent agreement on these questions. For example, from Genesis to Revelation, people are made right with God through faith, and this faith shows itself to be genuine by good works.
For example, the Bible teaches that Noah found grace in the eyes of the Lord, Abraham was justified by faith, Jesus said that the work of God was to believe on Him who he sent, and Paul talks about justification by faith. Not one author contradicts the rest by saying that a person can save themselves by earning salvation by their record of good works, as in all other religious systems in the world.
Even the use of words as symbols, as shown in The Bible Can Be Proven, chapter 1, is consistent across the whole Bible, which is remarkable considering the changes in cultures and meanings of words over time.
The Bible is not sixty-six books but one book, written with the inspiration of One Mind.