The ultimate arbiter of what is true is not your intellect or reason or experience. Although these are valuable, and are gifts from God, they are corrupted by sin. The ultimate authority is not what you think, or how you feel, but “what does the Scripture say?” (Rom 4:3; Gal 4:30). Over 400 times in the Old Testament, we read “thus saith the Lord” (you will find about 2/3 of these in Jeremiah and Ezekiel). The phrase conveys authority. God has the final word.
In all of Scripture, God is speaking, and we need to listen. We don’t judge the Bible by our standards; we let the Bible judge us. We don’t tailor our understanding of a Bible passage to match our established practices; we adjust our practices to accord with the Bible. We don’t minimize verses of the Bible that convict us; we thank Him for graciously speaking to us. We don’t mythologize accounts in the Bible that appear to contradict the laws of nature; we worship the God Who transcends nature. The Bible is God’s authoritative revelation to man.
When reading the Bible, there are going to be times that its truth seems to leave questions unanswered, or offends our sensibilities, or simply boggles our minds. “The question, therefore, that we must ask ourselves when faced with these puzzles is not: is it reasonable to imagine that this is so? Rather, we should ask is it reasonable to accept God’s assurance that this is so? Is it reasonable to take God’s Word and believe that He has spoken the truth, even though we cannot fully comprehend what He has said? The question carries its own answer. We should not abandon faith in anything God has taught us merely because we cannot solve all the problems which it raises. Our own intellectual competence is not the test and measure of divine truth. It is not for us to stop believing because we lack understanding, but to believe in order that we may understand¹.” You should read that quotation again. Carefully.
None of the above implies that our reliance on Scripture is irrational. There are plenty of sound reasons to believe the Bible. Research in history, archaeology, and ancient Biblical manuscripts are part of that evidence. But your main source of confidence in the Bible’s reliability will prove to be the Bible itself. It is a unique book. It is the Word of God Who does not lie (Titus 1:2).
This thinking will undoubtedly pose some problems in your interactions with an unbelieving world, which touts the theories of science and use them to mock the Bible. If there appears to be a disagreement between science and the Bible, there are two possibilities: either we do not properly understand the Bible, or there is an error in the science. Be clear that, as Christians, we need not be afraid of scientific study. It does a great job of explaining much in the natural world. But a Supernatural God, the Creator of the natural world, has spoken, and He has the final word.
¹J.I. Packer, “Fundamentalism” and the Word of God (Eerdmans, 1958), 109.