The reason why the Bible is the Word of God is that it has strength behind it. The little nation of Israel has great strength. Israel has existed possibly longer than any other nation. The Israel people hold that the Old Testament is truth. The only reason why they hold the Bible as such for as long as they have, is because there is strength in the Bible.
You constantly throw out this argument of strength in the Bible making it God's word. There is no strength in any book, rather people themselves find meaning in the words of a book that gives them the resolve to do what they need to do - there are many self help books out there that people use.
To say the words in the Bible are also God's words is a fallacy - the words in the Bible are man's words, stories passed down through the years by word of mouth before finally being collated and written into a single book. I always found it ironic that one of the first things we did in religious studies was play Chinese Whispers, yet we were expected to accept the writings in the Bible as the ultimate truth. If God actually existed and wanted his words to be passed onto man, he could have willed a paper book into existence with his words written inside when he
first created man. Did this happen? Nope. Instead the closest thing we supposedly have is some commandments inscribed in stone hundreds of years
after the creation of man.
When a person reads a book, the words that remain in his memory do not sit in his brain in book form. Rather, RNA converts into patterns of brain DNA that correspond to the words that he read. Whenever bio-electrical activity stimulates these particular chunks of DNA, the result is an activated memory of the words in the person, that correspond to the thing that he had read.
At the same time, a new record is created by new RNA turning into DNA, showing his remembering, and the reactions he had to the remembering. Generally this new memory is the one that is remembered the next time the person remembers the words.
At the next remembering point, a third memory is made overlaying the first two. The other two memories remain, but are seldom accessed, except when the memory needs to be reinforced in the consciousness in some way, or by haphazard stimulation during dreams.
God wrote His law in the minds and hearts (in the brains, chemically) of the first people. All people have it via genetics. Most people simply ignore it intentionally until the memory is dulled within them. If there had been no sin, the Bible wouldn't have been needed. Why not? People would remember the law written on their hearts perfectly, and wouldn't need a Bible to re-show it to them.
The Bible has been written for two reasons:
1. To show the law that has been forgotten;
2. To show God's forgiveness for man through the salvation He provides in Jesus.
In the same way that God has the ability to create people (a much harder thing than writing a book), He also has the ability to direct His people in ways so that they write the thing that He wants. The whole history of the coming into being of the Bible, and the contents thereof, show that it had to have been done by God. Why? Because it could never happen the way it did without Divine guidance.