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 3:16-17 ESV
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 1:21 ESV
The 66 books of the Bible were written by forty different men over a two thousand year period. Each author comes with his own personality, his own perspective and his own writing style. The style of Jonah is very different from the writings of Jeremiah, Paul has a different approach to an epistle than does James or Peter. The main thing they have in common, however, is the inspiration of the Holy Spirit guiding their writings.
The theological term is “verbal plenary inspiration”. Simply put, this means that every word (verbal) in every passage (plenary) is given by God through the hands of men (inspiration). God supernaturally guided the biblical authors to write the exact things that He wanted expressed. Everything from the genealogies in Genesis to the words of Jesus is the inspired words of God. All parts of the Bible are of divine origin and carry divine authority.
It is worth pointing out that it is the original language that is considered divinely inspired, not the translations. Translations are the tireless work of brilliant scholars but they are translations of inspired scripture and not inspired themselves. Much to the dismay of the King James only crowd, God did not inspire translators in the same way He inspired the authors. Most modern translations are trustworthy and certainly necessary for the spreading of God’s word, but no one translation is divinely inspired in the way the original manuscripts are. We have many copies of the original manuscripts in their original language so we can return to the original language for clarification of any passage.
If the Bible is inspired by God (ie. The Word of God) then it carries the authority of God. In other words, if the Bible says it then God says it. Bear in mind that there are some cruel actions taken be men recorded in the Bible. To say that the Bible is inspired and therefore authoritative does not mean that God wants you to kill your brother like Cain did, but it does mean that God says Cain killed Abel. Paul tells us that all scripture is useful, so the story of Cain and Abel is useful, not to tell us to kill our brother but to teach us that murder is punished by God who seeks justice for the spilling of blood. In contrast Jesus tells us to love our enemies and James tells us to rejoice when we are persecuted. Unlike the stories that contain instruction, these two references are examples of commands that God does want us to obey.
If the Bible is the inspired word of God then it cannot contain any errors or inaccuracies or contradictions. Many historical locations, events and individuals are mentioned in the Bible. If it could be proven that there was never a king in Israel named David as the Bible claims than the entire life of David must have been fabricated. If the life of David is a fiction than how can we trust that the life of Daniel, or Paul or even Jesus is not also a fiction? Instead of archaeology managing to disprove a portion of scripture, what if the book of Acts revealed that there never was a king named David. Now instead of historical error, we are dealing with a major contradiction. If such contradictions are in the Bible which part of the Bible are to hold up as true? How can we trust any other part of the Bible? How can we trust the God who claims to have inspired the Bible to be honest and trustworthy if His book is not entirely honest and trustworthy? Incidentally, archaeology found prove of King David in 1993, see the link below for details.
Since it was written the Bible has been under constant attack. Skeptics have attacked its historical accuracy and overall authenticity, but the Bible remains relevant and archaeology continues to prove its reliability, which only further proves its claim of divine authorship.
Truthful words stand the test of time, but lies are soon exposed. - Proverbs 12:19 NLT
Heaven and earth will disappear, but my words will never disappear. - Matthew 24:35 NLT
bibleinfo.com: Bible Authors
biblicalarchaeology.org: Proof of David