Premise A: Every utterance of God is perfect, and thus free from error.
Premise B: All the truth claims of the Bible writers are the utterances of God.
Conclusion: All the truth claims of the Bible writers are free from error.
Premise A is supported by the teaching that God cannot lie (Titus 1:2) and that He knows everything (I John 3:2). God cannot say anything contrary to the way things really are. He is morally perfect and will not lead anyone astray, especially since He is omniscient. Bible writers declare that the words of God are pure (Psalm 12:6, Prov. 30:5). Paul calls Scripture the “word of truth” (2 Tim. 2:15). According to Romans 9:1, the truth excludes the possibility of lying. There is nothing spoken by God that is contrary to what is really real.
Premise B is supported by II Timothy 3:16 (“All Scripture is God-breathed”), and other scriptures that refer to the words of Moses and the prophets as actual words of God (Romans 3:2, Acts 28:25).
That is the deductive argument for inerrancy. If Premise A and B are true, then the conclusion (that all of the truth claims of the Bible writers are free from error) must be true. If the conclusion is true, then we must approach Scripture from the stance of faith, trusting that when properly interpreted there will be found no error in Scripture, no matter how small. Nothing will be stated as a fact (by the Bible writers themselves, not necessarily those they quote) that does not correspond to the way things really are.