A testament that the Bible truly is the word of God is that while written by many authors it still agrees with itself. It is consistent. It has coherence. There is a common thread, although different attributes of God are emphasized at different times (leading people to make ignorant insinuations). There are no contradictions that cannot be explained. How can you get 40 people writing over 1500 years, from vastly different walks of life to somehow agree upon something...just about everything... as controversial and divisive as God, His attributes and character? The answer is that all these authors were inspired by God himself, who is consistent and faithful. They truly had "God encounters!"
"The Bible is a book concerned primarily with man's relationship with God. It is, among other things, a historical story about humans becoming separated from God (the Creator) because of our sinfulness and rebellion. Since it concludes with God's rescue of His people from their own sinfulness and the restoration of all things to Himself, it’s also a story with a happy ending. The Bible is not a single work by a single author (unless one were to call God, Himself, the author). It's a collection of ancient writings, written over a period of 1,500 years, by approximately 40 different authors. These writings are compiled in a book we now call "the Bible." The Bible consists of 66 "books" in total, divided into two large sections: the Old Testament and the New Testament. The word "Bible" comes from the Greek word "byblos," which simply means "book." The earliest Christians were, for the most part, of Jewish heritage. As such, they considered Jesus to be the continuation and fulfillment of the Old Testament (the first section). The second large section is called the New Testament. The writings in the New Testament comprise the essentials of the Christian faith, beginning with the genealogy and life of Jesus. There are 39 books in the Old Testament and 27 books in the New Testament. Christians believe that these 66 books form the sum total of God's revelation to mankind about Himself, the state of man, and God's plan for redemption." (Excerpt from Consider the Evidence pg 7-8)