When Christians think and speak about apologetics—about defending the Christian faith against the attacks of unbelievers—it can sometimes be the case that Scripture itself is one of the furthest things from their minds. When endeavoring to defend the faith, many of us think immediately of archaeology, of philosophical arguments, of scientific proofs and rebuttals, of canonicity and textual criticism, and of refutations of classic atheistic arguments. While all those things have their place in a well-rounded, robustly prepared defender of the faith, it’s unfortunate that Scripture can be one of the last places we think to inform our apologetic methodology. But in point of fact, there are many passages in the Bible that teach us much regarding issues of defending the faith and reasoning with unbelievers. I’d like to explore some of those lessons today. A God-Dependent EpistemologyOne of the tasks of apologetics is to determine proper grounds for believing in something. This discipline is called epistemology—the study of how we know what we know. Proverbs 1:7 states simply that the fear of the Lord is the beginning of knowledge. In this short statement, God declares to us that the only sure foundation of knowing anything properly is to fear and worship Him. To reject the existence of God—or even to admit the existence of God but to fail to worship Him as He requires—precludes one from knowing anything soundly. That’s why the Psalms repeat that it is the fool who has said, “There is no God” (Pss 14:1; 53:1).A Biblical AnthropologyIn fact, the Bible tells us that God has clearly made Himself known to the world, such that there is no excuse for rejecting His existence. Romans 1:20 says, “For since the creation of the world His invisible attributes, His eternal power and divine nature, have been clearly seen, being understood through what has been made, so that they are without excuse.” On top of this, all people are created in the image of God (Gen 1:26–27) with the law of God written on their hearts, such that their conscience naturally informs them of their rejection of Him (Rom 2:14–15). These texts teach us that the unbeliever’s primary problem is ethical, not intellectual. The problem with the unbelieving mind is not that it lacks the right information or enough evidence. Rather, the unbeliever knows the truth, but actively suppresses that truth in unrighteousness (Rom 1:18) because he loves his sin (John 3:20). All of the evidence he is presented with will be filtered through a sinful worldview, because, as Paul says in 2 Corinthians 4:4, his mind has been blinded to glory. You can present evidence to a blind man all day, but unless his blindness is cured he’ll never even be able to evaluate it rightly.Implications of Depravity for ApologeticsThis leads the Christian to at least three conclusions. First, our apologetic method is inextricably linked to the preaching of the Gospel. The Holy Spirit must open blind eyes before evidence can be interpreted rightly (2 Cor 4:6; cf. 1 Cor 2:14). Secondly, there is no such thing as neutral thinking, and in our apologetics we must never treat an unbeliever as if he reasons autonomously. Everyone has presuppositions. We must keep in mind the unbeliever’s presuppositions when we engage him, and we must not surrender our own—for they are the presuppositions of Scripture, which is to say, the presuppositions of reality. Finally, because our thinking is so infected with sin, the only proper foundation for knowledge is God’s revelation. Scripture must be fundamental in our apologetic encounters.1 Peter 3:15A text with great implications for apologetics is 1 Peter 3:15. Peter expected that the Christians’ endurance of great persecution would cause outsiders to ask them why they were so hopeful in the midst of such suffering. He tells them, “Sanctify Christ as Lord in your hearts, always being ready to make a defense to everyone who asks you to give an account for the hope that is in you, yet with gentleness and reverence.” This teaches us a number of things. First, Christians must always be ready to defend the faith accurately. That means we should make whatever preparations necessary to be equipped in this regard. Secondly, it presumes that a defense is to be made against attacks on the faith. A major function of apologetics is to answer misunderstandings and misrepresentations of Christianity. Thirdly, it teaches us about our attitude. Many Christians engage in apologetics with a pugnacious and contentious spirit. Instead of this, the Christian apologist is to defend the faith with gentleness and reverence.Defensive and OffensiveNot only is apologetics concerned with defending the faith from outside attack, it is also concerned with refuting the claims of non-Christian belief systems. Paul uses graphic language to make this point clear: “We are destroying speculations and every lofty thing raised up against the knowledge of God, and we are taking every thought captive to the obedience of Christ” (2 Cor 10:5). Thus, our task is not only to show that Christianity is reasonable, but to demonstrate that other worldviews are unreasonable. According to Scripture, apologetics is both defensive and offensive—both negative and positive.The Necessity of WisdomFurther, Proverbs 26:4–5 teaches us that wisdom is required in apologetics. There are certain times when we must not answer a fool according to his folly, lest we be like him. Yet there are other times when we indeed must answer a fool according to his folly, lest he be wise in his own eyes. We must pray for wisdom from God to know when one or the other of these is the appropriate course of action (cf. Jas 1:5).Biblical ExamplesScripture also generously affords us some observable examples of Christian apologetics. In the opening verses of his Gospel, Luke makes his purpose for writing known: he wanted Theophilus to know the exact truth about the things he was taught regarding Jesus Christ (1:4). For Luke, this was to be accomplished by a careful investigation of “everything” (1:3)—including eyewitness testimony (1:2)—and presenting it in “consecutive order.” Luke was “making his case,” so to speak, for the reality and veracity of the doctrine of Christ.In Jesus’ interaction with the Pharisees in Matthew 12, we see Him contradicting a claim that does not correspond to reality (12:24) by reasoned arguments. He reduces their argument to absurdity (12:25–26), shows them to be inconsistent (12:27), and offers His miracles as proof that He is King (12:28). Each of these components provide insight into a biblical apologetic methodology.In Acts 17, we can learn from the Apostle Paul’s preaching Christ to the philosophers of Athens. We must understand that he argued specifically contrary to the presuppositions of his hearers (Ac 17:24–26, 31), making no attempt to find an initial point of agreement and then pursue a neutral method of argumentation. When he reasoned with the Jews who, at least in theory, accepted the authority of Scripture, he began with Scripture as evidence for Jesus’ lordship. Yet with pagans with no access to the Hebrew Bible, he argued from creation and challenged them to turn from their idolatry. In either case, his epistemological framework had not changed, for the Gospel he preached was “according to the Scriptures” (1 Cor 15:3–4). His practice was to preach the truth, to give reasons for his viewpoint, to present the Gospel of Christ, and to demand for repentance (Ac 17:30–31).Can you think of any other biblical texts that inform the way we defend the faith once for all delivered to the saints?