How the Bible was Written
Different books of the Bible were written by different people. However, these writers have several features in common. The Apostle Peter comments on one of these features in his second letter:-
"For we did not follow cleverly devised myths when we made known to you the power and coming of our Lord Jesus Christ, but we were eyewitnesses of his majesty." (2 Peter 1:16)
This passage makes the point that the writers of the Bible were eyewitnesses of the events they describe. Peter is referring to one event in particular here, but there is great emphasis on the eyewitness nature of the writings throughout the New Testament (the Old Testament contains explicit personal testimony, rather like the letters in the New Testament).
The main point about the writers of the Bible, however, is that they were inspired by God. This means not only that the message of the books they wrote is from God, but even that the wording of the Bible is what God intends. Again, there are many places where the writers of the Bible made this claim for their words; here is one from Peter’s second letter:-
"…knowing this first of all, that no prophecy of Scripture comes from someone’s own interpretation. For no prophecy was ever produced by the will of man, but men spoke from God as they were carried along by the Holy Spirit." (2 Peter 1:20,21)
The point that is being made here is that the words of the prophets originate with God. He might achieve this by a number of different mechanisms, but the result is a book which contains the words and message that God intends.
This claim also appears in a letter by the Apostle Paul:
"But as for you, continue in what you have learned and have firmly believed, knowing from whom you learned it and how from childhood you have been acquainted with the sacred writings, which are able to make you wise for salvation through faith in Christ Jesus. All Scripture is breathed out by God and profitable for teaching, for reproof, for correction, and for training in righteousness, that the man of God may be complete, equipped for every good work." (2 Timothy 3:14-17)
This passage refers to the Scriptures available to Timothy at the time. This would, of course, include the Old Testament, but a considerable part of the New Testament was also available at the time (1 Timothy 5:18 quotes from Luke 10:7 and describes it as “Scripture”) - there were also several other letters by Paul.
The passage also tells us that all this writing comes from God - that God is behind its writing. It also tells us that the Bible is complete - that it contains everything that is needed for understanding and for living the life required of us by God.
Every word of the Bible was written by a prophet inspired by God. The Bible is the only book that can make this claim. No other book, not even the Scriptures of other religious traditions, can make this claim.