I believe what the Bible claims for itself. It is not a product of man. It is a product of God.
One may reach the conclusion that the Bible is not a revelation from God. But, the Bible refers to itself as being the word of God. There can be no doubt that Jesus and the first century church accepted the 39 books of the Old Testament (the law and the prophets )as a direct revelation from God. Also, the apostles doctrine as being a revelation on the same level with the Old Testament.
2 Timothy 3:16-17. Paul wrote, "All scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness: that the man of God may be perfect, throughly furnished unto all good works." The words of the Bible are "breathed of God" (inspired).