The question of "How do we know?" is a question that does not cross our minds very often (unless you are a philosopher!); yet, it is a very important question.1 In approaching the question, we need to understand that each of us has developed a particular view about the nature of reality that is based upon an ultimate standard of interpretation. That is, each of us interprets (gives meaning to) the "facts" of the world by an appeal to that which each one believes to be the ultimate criterion for determining reality. This process of judging the facts takes place, we might say, automatically, so it is not usually something of which we are conscious.
On the basis of a standard, we all interpret the data that comes to us individually and categorize it as right or wrong, good or bad, true or false, helpful or unhelpful, desirable or undesirable, etc. This is what is meant when we say that we interpret the "facts" of our experience. The resulting interpretation of the particulars we encounter is what we call knowledge. We know that something is what we believe it to be because our ultimate standard for determining knowledge tells us that it is so. Therefore, all of our presumed knowledge is actually based upon that which we presuppose as the final arbiter of reality. This presupposition, or first-principle, is our supreme faith-commitment; that is, we believe that our chosen standard is the best and most reliable one.2 This presupposition is the starting point of all of our thinking and the basis for all of our predication of all our affirmations as to the quality, nature, or attributes of a thing (fact).3 So even though most of us have not given a lot of thought to this matter of an ultimate standard of interpretation, we all have one. And we all, consciously or unconsciously, interpret all the particulars we experience from the basis of an all-controlling presupposition.
That our starting point, our basic presupposition, is all-important, is evident: if it is sound, our interpretation will be sound; if it is false, our interpretation of the facts will be defective. The goal, therefore, is to have the right presupposition. But what is the right presupposition; what is the proper standard of interpretation; what is the unfailing faith-commitment that will lead us to true knowledge? Men have different answers to this question. For example, the rationalist says that human reason is the standard. The empiricist says that it is sensory experience. The hedonist says that it is pleasure. The pragmatist says that it is the thing that works. The irrationalist says there is no ultimate standard because all is pure chance, pure contingency. The religionist says that it is his religion. The Christian says that it is the God of the Bible. In the midst of all this babble, how does the Christian know that God is real and the Bible is true, and that, therefore, all other presuppositions are false?
In the quest for the right first-principle of knowledge, the matter of authority is an inescapable concept. Who has the authority to determine the nature of reality? Who has the warrant to say, "This is the first-principle of knowledge"? When you get down to it, there are really only two possible sources of authority, two possible standards in the sphere of epistemology: God or man. Either God is ultimate, or man is ultimate. You either begin with the transcendence of God as Creator, and of His absolute right to determine the meaning for all facts and the standards for all conduct, or you begin with autonomous man and his categorical right to define meaning and establish standards of action that suit him. Either God is the judge and interpreter of reality, or man is the judge and interpreter of reality.
This leads to a second factor. If man is the authority, then the instrumentality for interpretation is his own mind and intellect his own reason. But if God is the authority, then the means for interpretation must be revelation; that is, God must make His mind known to man in some understandable and verifiable way so that man can think God's thoughts after Him and interpret the facts of the universe in accordance with God's sovereign will and purpose. The orthodox Christian is not in doubt as to Who is the authority and what is the instrumentality of interpretation. The Christian believes in Almighty God as the Creator of all things and the Sovereign Determiner of all facts, and that the Bible is the revelation of God to man (it is the Word of God) so that man might understand God's creation, man's place in it, and the nature and meaning of all things.
The fact of the existence and authority of God and the fact of the Bible as the infallible Word of God are, by the nature of the case, "self-authenticating" truths. What does this mean? It means that the truth concerning the attributes and existence of God is so great, so fundamental, and so certain that it cannot be proved by reference to anything else. If God is ultimate, then there is nothing that can be employed to verify Him; if there were, that thing would be more ultimate than God, for He would have to be defined in reference to it. God has declared Himself as "I AM THAT I AM" (Ex. 3:14). He is the eternally self-existent, self-contained, self-sufficient, self-revealing One Who is faithful to His covenant. He is the sovereign Creator Who made all things, decreed all things, and defined all things, but Who in Himself is determined by no one or no thing. Therefore, God does not seek to prove His existence to men. His existence is the very ground for the existence of man and of the creation. In history, and in the Scripture that records that history, God presents Himself to man as God in all His splendor and glory, and as nothing else or nothing less.
The Bible is also, of necessity, self-authenticating. As the Word of God, it is ultimate in its authority. It cannot appeal to the word (judgment) of any other to verify its nature without denying its own nature. For example, if the word of man is necessary to establish the Bible as the Word of God, then man's word is the ultimate authority; if experience is required to establish it, then experience is supreme, etc. As the Word of the Creator, the Bible alone is infallible in its interpretation of man and of the creation.
If the existence of God and the nature of the Bible as the infallible Word of God are self-authenticating truths, then why do not all men embrace these truths? The answer is twofold.
First, man is in ethical rebellion against God. This means that he knows that God is his Creator and that the Bible is the Word of God, but he revolts against these truths. As a creature, he knows that God exists; but as a sinner, consumed with his own importance, his own desires, his own autonomy, he hates God and the intrusion that God represents to his plans. So, he actively suppresses his knowledge of God so that he can pursue his own agenda (Rom. 1:18-21). Man does not perish for a lack of knowledge about God man's own being and all creation clearly testifies of God's glory, power, and Godhead (Rom. 1:19-20; Ps. 19:1-6) he perishes because he sins against the knowledge that he does have. This rebellion began in the Garden of Eden when Eve chose to establish herself, her own reason, as the ultimate reference point of predication (initially, concerning the tree of the knowledge of good and evil), and thus claimed her own autonomy. Eve knew of God and of His interpretive word, but did not believe that God could be ultimate; so, she reinterpreted the nature of God to suit her own autonomy (made God into a god of her own imagination, cf. Rom. 1:23, 25). This is what men are about today. Like Eve, they establish themselves, some other man, or some other aspect of the creation as their ultimate reference point for determining knowledge; they interpret the facts of their experience on the basis of their chosen presuppositions. Then, if they wish to retain the concept of God (a concept that man finds hard to part with), they fashion a god of their own liking (or accept one already fashioned by other men) that is far different than the sovereign, self-contained God revealed in Scripture.4 It must be so, if they will have a god, because their presuppositions chosen as they are in the pursuit of rebellion, deny the existence of the Creator/God of Scripture.5
Second, those who do believe in the existence of God and the divine inspiration and infallibility of the Bible do so, not because of some set of rational or sensory proofs, but because of the grace of God that has changed them from rebels to worshippers. When the Spirit of God regenerates a man, that man's epistemology is radically changed: he casts off his own autonomy, buries his false presuppositions, and embraces God as He is and the Word of God as the only true interpretation of his condition and its solution. This being done, the erstwhile rebel now submits to God's authority and puts his faith in the gospel. In salvation, a man comes to embrace God and His Word as ultimate. In sanctification, this first-principle, this absolute presupposition, works itself out in the life of the believer as he learns to interpret all facts, all areas of life, according to God's Word.
We Christians know that God exists and that the Bible is true "by the inward work of the Holy Spirit bearing witness by and with the Word in our hearts."6 This witness enables us to reorient all of our thinking so that now, with our self-imposed, alien presuppositions removed, we are able to see that all creation shouts of the glory of God. We learn that our unbelief was never a problem of the lack of evidence (it is everywhere), but due to eyes that had willfully been blinded by false presuppositions derived from a rebellious heart that said, "I will determine truth and falsehood, and good and evil for myself."
What, then, is the nature of apologetics? "Apologetics," as a theological discipline, refers to the defense of the Christian Faith against the attacks of all forms of unbelief. Apologetics gives a Biblical defense of the reason for the hope that is within us (1 Pet. 3:15). But, in terms of our encounter with an unbelieving world, what is the purpose of this defense? Many Christians believe that the goal of apologetics is to open minds and hearts to the truth of God by showing unbelievers through rational proofs and logical argumentation that the Bible is trustworthy and that Christ is the Savior. But this is not the purpose of apologetics. The purpose of apologetics, as Greg Bahnsen has well stated it, is not to open hearts but to close mouths. That is, we show the unbeliever the foolishness of his own worldview that by rejecting the sovereign Creator/God of the Bible, he has no basis for meaning, rationality, or prediction; no answer to the question of the one and the many; no hope for the future; and, since all unbelieving thought is bankrupt, he can only live his life by stealing from the worldview of the Christian then, having shut his mouth, we present to him the claims of Christ without compromise. Only God can open the heart of man to receive the testimony of Christ, and the instrumentality He has chosen to accomplish this is the Word and Spirit.
Since man is a rebel who is willfully suppressing the knowledge of God that is in him and around him, we know that the problem for any particular man is not a lack of evidence for God. Man's problem is sin. He has set himself up as ultimate. Using the Word of God, we must convict him of his sin and show him the redemption that is in Christ Jesus. If the sinner raises objections, we should patiently answer those objections. But in our answers we must never give the unbeliever the idea that he has the right to sit in judgment of God's truth, or that he is the ultimate judge of what the Scriptures say. We must not appeal to his reason as if that determines the matter. We, as faithful ambassadors, must deliver the Word of our sovereign God as the Word of a sovereign God who sits in judgment of all men and commands all men everywhere to repent. We must trust in the self-authenticating Christ of Scripture to work His sovereign will for the glory of His own name.
1. The question of, "How do we know?" belongs to the field of study that we call "epistemology." Epistemology concerns itself with the investigation of the origin, nature, and methods of knowledge.
2. We call this a "faith-commitment" because it is something we accept without any proof beyond the presupposition itself. In other words, there is nothing beyond our chosen standard that we can appeal to establish it. For example, if we look to reason as the ultimate standard, we do so because it alone appears reasonable to us. If we sought to prove that reason was the true standard by an appeal to sensory experience, then what we have done is set up experience as our ultimate standard because it is used as the basis for our predication concerning reason.
3. However, men often act and believe in a way that is inconsistent with their basic presuppositions. This is due to the fact that man is a complex being with many factors influencing his mind. In spite of this, it is still true that a man will ultimately rely on his chosen standard of knowledge to interpret the facts of his experience. To be aware of one's presupposition and to act in accord with it on a consistent basis is to be an "epistemologically self-conscious" individual.
4. This is the origin of the many religions of the world (except, of course, Biblical Christianity). These religions are the creations of men (with assistance from Satan and his demons) for the purpose of retaining the concept of God while conveniently denying His eternal power and Godhead.
5. This analysis does not intend to convey that all men consciously and with deliberation follow these steps. Culture, parental sins, and the like determine the rebellious presuppositions of many. Men do not always have to plot their steps in a definitive way because other sinners have already done it for them; being in the same ethical rebellion, they follow in the paths of their predecessors.
6. Westminster Confession of Faith, I, 5.