How do we know that every word in the Bible is the Word of God?

Scripture reveals that while human authors penned the Bible, the ultimate author is God Himself. As stated in 2 Peter 1:21, '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.' This truth underscores that every word is not merely the opinion of men but the unchangeable words of God. The authenticity and divine authorship of Scripture give believers confidence that every part of it is pertinent and applicable to our lives today.