Circular reasoning is an argument in which a person begins with the point that he or she is trying to prove. Well-meaning Christians who seek to prove the Bible is God’s Word have often used this fallacy. For example, a person might say, “The Bible is true because it says it comes from God.” While the argument is true, it is not a valid logical argument, because it uses the conclusion to prove its conclusion.
In contrast, to say something is self-authenticating is to say it is true without offering additional proof. A good example is a notarized document. A notarized document can be submitted as proof in a court of law because it has already been authenticated as true in another context. Some claim the Bible is self-authenticating in the same sense, because it has been proven by other means, such as external history or archaeology. While this is true to some extent, it is not true in the same sense as a notarized document.
To show that the Bible is self-authenticating, we can look at some ways the Bible can be demonstrated to be true through external means. There are two means of logical reasoning, deductive and inductive reasoning. Deductive reasoning uses the premises of an argument to prove the conclusion is certainly and undeniably true, such as 2+2=4. Inductive reasoning instead compiles evidence to show the likelihood of a conclusion’s truth. This is the better option for argumentation about the accuracy of Scripture.
To provide inductive evidence for the trustworthiness of the Bible, you can offer many lines of evidence to increase the likelihood that it is true. This can include external history that supports the Bible’s events, archaeology, early manuscripts, the quality of agreement between manuscripts, and other lines of evidence. These means can provide ample support to show the Bible is trustworthy and accurate; yet the view that the Bible is inerrant is based on a theological argument.
Biblically speaking, Scripture claims the Bible is God-breathed (2 Timothy 3:16–17). If it is breathed by God, and God is perfect, Scripture must be perfect (Psalm 19). Another way to say this is that God is true (Romans 3:4) and God breathed out Scripture (2 Timothy 3:16–17); therefore, the Scriptures are true. Many have argued from these and other passages that the Bible is self-authenticating, that it proves itself true within its own words. However, this is a deduction based on Scripture itself and is unacceptable to anyone who does not already agree with the accuracy of the Bible.
While a believer who is sharing with a skeptic of the Bible should be aware of these issues, it is important to use evidence with a skeptic that he would accept as credible. This approach will provide a common ground for discussion that can lead to further consideration of the reliability of the Bible without making assumptions rejected by non-believers.