Christians claim that the Bible is not just like any other book. It is a book that is said to be divinely inspired. God moved the human authors to write books that contain the content God intends to communicate without entirely bypassing the human author. What follows from this? Let’s say it’s true. What properties does a divinely inspired book have that other books may not have? The very least we can say is that if scripture is divinely inspired then what scripture asserts is true. God cannot lie or be mistaken in any claim he makes. If the Bible is divinely inspired then everything it affirms as true is a statement God intended the human author to make. The uniqueness of this feature of the Bible is well illustrated by Plantinga:
Scripture itself is taken to be a wholly authoritative and trustworthy guide to faith and morals; it is authoritative and trustworthy, because it is a revelation from God, a matter of God’s speaking to us. Once it is clear, therefore, what the teaching of a given bit of Scripture is, the question of the truth and acceptability of that teaching is settled. In a commentary on Plato, we might decide that what Plato really meant to say was XYZ; we might then go on to consider and evaluate XYZ in various ways, asking whether it is true, or close to the truth, or true in principle, or superseded by things we have learned since Plato wrote, and the like; we might also ask whether Plato’s grounds or arguments for XYZ are slight, or acceptable, or substantial, or compelling. These questions are out of place in the kind of Scripture scholarship under consideration. Once convinced that God is proposing XYZ for our belief, we do not go on to ask whether it is true, or whether God has made a good case for it. God is not required to make a case.
The problem with this is that we need some warrant for believing that the Bible is in fact inspired. What warrants the belief that the Bible is divinely inspired? The most common suggestion is that there is good evidence for the divine inspiration of the Bible. Gordon Clark, for example, argues, “it is perfectly reasonable both to accept that God’s self-witness must be the ultimate guide to divine thoughts, feelings and desires and also to investigate rationally whether a particular writing that alleges to be from God actually is from God.” Evidentialism seeks to prove the antecedent in the hypothetical: “if the Bible is God’s self-witness, then its content is the ultimate source of knowledge regarding the divine thoughts, desires, plans, and instructions.” The kind of evidence required is largely historical. For example, one might present a historical case for the resurrection. If Jesus was resurrected, then his claims about himself and about scripture are plausibly of divine origin.
Not everyone is convinced by the evidentialist project. Plantinga argues that even if good evidence were available such evidence would not warrant the consequent. He suggests that even if maximal probability is obtained for the belief that a given corpus of writing is divinely inspired it can only yield “belief that it is fairly likely that the New Testament is the Word of God.”An alternative view is that the external witness of the Bible to its own inspiration coupled with the internal testimony of the Holy Spirit provides sufficient warrant for belief that the Bible is inspired by God. The Westminster Confession of Faith states:
Under the name of Holy Scripture, or the Word of God evidence itself to be the Word of God: yet notwithstanding, our full persuasion and assurance of the infallible truth and divine authority thereof, is from the inward work of the Holy Spirit bearing witness by and with the Word in our hearts.
On this view, the Holy Spirit works in the heart of the believer to impel the belief that the books of the Bible are divinely inspired. The external testimony of scripture assures the divine origin of scripture when coupled with the internal testimony of the Holy Spirit.
Okay, you might say, what evidence do you have of that claim? Well, I have at least one piece of evidence: me.
I believe the Bible not because of a good argument, but because God has given me his Holy Spirit and has made it so that when I read the Bible I am able to affirm the truth of what I read. I am able to believe that what scripture tells me about my sin and God’s salvation in Jesus Christ is true. Given what the Bible says about history, some of which is amazing and includes the resurrection of Jesus Christ, it is amazing that I should believe any of it! But, I do.
 Alvin Plantinga, “Two (or more) Kinds of Scripture Scholarship” in Behind the Text eds. Craig Bartholomew, Stephen Evans, Mary Healy and Murray Rae (Grand Rapids: Zondervan, 2003), 22.
 Westminster Confession of Faith, Ch 1.4.
 I’m leaving out a discussion of assertions made by people recorded in scripture that are in fact false.
 Plantinga, 25.