Biblical Doctrine: A Systematic Summary of Bible Truth (God the Father: The Existence of God)

Scriptural Assertions

The Knowability and Incomprehensibility of God

Assessment of “Natural Proofs”

“In the beginning, God …” (Gen. 1:1). The Bible does not begin with a rationalistic argument for the existence of God but rather assumes that he exists, that he existed before the beginning of all things outside himself, and that there is only one God. Theology proper, as with all other areas of systematic theology, is properly derived from God’s own testimony in his inspired, inerrant Word, the Bible. One’s concept of God does not come “from below,” from human reasoning about the universe, because human reason is finite in its components and operations, corrupted by indwelling sin, and therefore never able of itself to derive an accurate understanding about God, who is infinite and holy. Proof for God’s existence must come, first and foremost, from God’s testimony about himself. He has provided irrefutable proofs for his existence in the Bible.

Scriptural Assertions

This volume does not seek to prove the existence of God from human reasoning but rather presupposes that the God of the Bible exists and endeavors to set forth what the Bible teaches about God. The only reliable proof of the existence of the true God consists of statements from and about him in his inspired Word. God must not be excluded from testifying about himself. Quite the contrary, his testimony, given by his own inspiration, must be accepted as unique and perfectly reliable. Scripture alone is inspired, or “breathed out by God” (Gk. theopneustos, 2 Tim. 3:16), so one must first look to the Bible alone for evidence that is pure and that transcends the limitations of human intellectual finiteness and corruption. Other evidences of God’s existence—for example, those in the created realm (Rom. 1:19–20)—must be evaluated and accepted only as they align with the Bible’s statements about God.

Scripture asserts the existence of “the only true God” (John 17:3). The Bible begins with the foundational presupposition that God existed “in the beginning” (Gen. 1:1). So every statement from the Bible about God’s nature and actions is proof from him of his existence.


For example, the Bible requires that everyone who wants to be properly related to God must first believe that he exists: “Whoever would draw near to God must believe that he exists” (Heb. 11:6). To do otherwise makes one a fool. Scripture calls those who in their heart and thinking do not believe that God exists “fools” and “wicked”:

The fool says in his heart,

“There is no God.” (Pss. 14:1; 53:1)

In the pride of his face the wicked does not seek him;

all his thoughts are, “There is no God.” (Ps. 10:4)


The Bible repeatedly states that God is eternal. God is without beginning, without ending, and without succession of moments in his experience and knowledge of himself and of all reality outside himself. In the Bible, God is called “the eternal God” (Deut. 33:27). Psalm 90:2 says that God existed eternally in the present before the world was created: “Before the mountains were brought forth, or ever you had formed the earth and the world, from everlasting to everlasting you are God.” In Isaiah 41:4, God declares, “I, the Lord, the first, and with the last; I am he.” Isaiah adds, “Thus says the Lord, the King of Israel and his Redeemer, the Lord of hosts: ‘I am the first and I am the last; besides me there is no god’ ” (Isa. 44:6). And Isaiah 57:15 affirms that God “inhabits eternity.”


A final proof of God’s existence is his statements that he “is,” without dependence on anything else for his life. God told Moses by what name Israel was to know him: “God said to Moses, ‘I am who I am.’ And he said, ‘Say this to the people of Israel, “I am has sent me to you” ’ ” (Ex. 3:14). God is. So he depends on nothing for his existence. This inference from God’s covenantal name is reflected in the apostle Paul’s words: “For from him and through him and to him are all things” (Rom. 11:36), and, “The God who made the world and everything in it, being Lord of heaven and earth, does not live in temples made by man, nor is he served by human hands, as though he needed anything, since he himself gives to all mankind life and breath and everything” (Acts 17:24–25).

One could go on to multiply biblical proofs of God’s existence from all the scriptural statements about God’s being and works. However, these suffice to show that God affirms his existence in the statements of the Bible as the primary, foundational, and foremost proofs by which people must believe that he does exist.

The Knowability and Incomprehensibility of God

Because God has revealed the fact of his existence in Scripture, he has given humans statements by which they can have at least some knowledge of him. The Bible makes God knowable to humans, to the extent that the content of the Bible reveals truth about him. Scripture teaches that man may know God truly, yet not exhaustively. In the classical terminology, God is truly knowable but not exhaustively comprehensible.


The Bible affirms that God can be known, even known in a personal relationship of friendship. He walked with Adam and Eve in the garden of Eden (Gen. 3:8). He appeared to Moses in the burning bush (Ex. 3:3–4). He gave his law to Moses on Mount Sinai (Exodus 19). In ancient Israel, God made himself present in the tabernacle and in the temple on the mercy seat on top of the ark of the covenant (1 Sam. 4:4; 1 Kings 8:10–11). Jesus said that God can be personally known (John 17:3). Jesus himself is the incarnation of God (Col. 2:9). The New Testament reveals that God indwells the church (1 Cor. 3:16), dwells within believers (John 14:23), and is the friend of believers (James 2:23).


Though God can be known truly, Scripture also reveals that God is not comprehensively or exhaustively knowable to humans in any aspect of his being or actions. Humans are limited to time and space and in Adam are corrupted by indwelling sin (Rom. 7:15–23), which has made them rebellious toward God and has darkened their understanding of God’s revelation in the Bible and in nature (2 Cor. 4:3–4; Eph. 4:17–19). God is eternal and holy, transcending time and space, infinitely omniscient, and absolutely morally pure. God alone is great. Man was created as a different and inferior order of being. Even in his originally created state, humanity could not know God exhaustively, but after the fall of Adam, even the knowledge humans can have of God is corrupted by sin.

The Bible unmistakably testifies to the fact that God cannot be fully known by humans, even apart from the darkening factor of their internal sinful corruption. Man cannot see God and live (Ex. 33:20; Lev. 16:2). God “dwells in unapproachable light, whom no one has ever seen or can see” (1 Tim. 6:16; see John 1:18; 6:46). The spiritual form of God’s essence is not revealed (Deut. 4:12, 15). The depths of God are known only by God (1 Cor. 2:11).

Going a step further, God cannot be fully searched out. Psalm 145:3 says, “Great is the Lord, and greatly to be praised, and his greatness is unsearchable.” The word “unsearchable” is a translation of the Hebrew ’en kheqer, “without searching.” The Hebrew root, khaqar, from which the noun for “searching” comes, is used in the Old Testament of “searching exhaustively.” For example, the same phrase is found in Isaiah 40:28: “Have you not known? Have you not heard? The Lord is the everlasting God, the Creator of the ends of the earth. He does not faint or grow weary; his understanding is unsearchable.” The same root word is used in its verbal form to speak of miners searching exhaustively in the earth for ore: “Man puts an end to darkness and searches out to the farthest limit the ore in gloom and deep darkness” (Job 28:3; cf. Job 11:7–8; 36:26). Compare other Old Testament expressions of God’s incomprehensibility:

These are but the outskirts of his ways,

and how small a whisper do we hear of him! (Job 26:14)

He does great things that we cannot comprehend. (Job 37:5)

Adding to the biblical affirmation of God’s incomprehensibility is the fact that he has not revealed to us all that he is or all that he knows. Deuteronomy 29:29 says, “The secret things belong to the Lord our God, but the things that are revealed belong to us and to our children forever, that we may do all the words of this law.” According to Revelation 10:4, John was commanded not to write something he had witnessed: “And when the seven thunders had sounded, I was about to write, but I heard a voice from heaven saying, ‘Seal up what the seven thunders have said, and do not write it down.’ ”

Finally, God’s incomprehensibility is seen in scriptural statements that God’s thinking transcends man’s intellectual capacity, process, and output. Psalm 139:6 says that God’s knowledge “is too wonderful for me; it is high; I cannot attain it.” Psalm 139:17–18 states that God’s thoughts are “more than the sand” in number. Psalm 147:5 declares that God’s “understanding is beyond measure.” God contrasts the superiority of his thoughts with the inferiority of man’s thoughts: “For as the heavens are higher than the earth, so are my ways higher than your ways and my thoughts than your thoughts” (Isa. 55:9). This incomprehensibility of God’s intellect is what Paul proclaimed in his explosion of praise in Romans 11:33–34: “Oh, the depth of the riches and wisdom and knowledge of God! How unsearchable are his judgments and how inscrutable his ways! ‘For who has known the mind of the Lord, or who has been his counselor?’ ”

When trying to search out God’s nature, one finds that it is infinitely beyond what can be learned or reasoned. This holds true with respect to any aspect of God’s nature. Grudem summarizes helpfully:

It is not only true that we can never fully understand God; it is also true that we can never fully understand any single thing about God. His greatness (Ps. 145:3), his understanding (Ps. 147:5), his knowledge (Ps. 139:6), his riches, wisdom, judgments, and ways (Rom. 11:33) are all beyond our ability to understand fully.… Thus, we may know something about God’s love, power, wisdom, and so forth. But we can never know his love completely or exhaustively. We can never know his power exhaustively. We can never know his wisdom exhaustively, and so forth. In order to know any single thing about God exhaustively we would need to know it as he himself knows it. That is, we would have to know it in its relationship to everything else about God and in its relationship to everything else about creation throughout eternity! We can only exclaim with David, “Such knowledge is too wonderful for me; it is high, I cannot attain it” (Ps. 139:6).

Assessment of “Natural Proofs”

Theology proper seeks to ground the knowledge of God’s existence in Scripture and to relegate all other evidence of God’s existence to secondary status, subordinate to Scripture’s assessment. Still, God has revealed himself by means other than Scripture. He has revealed himself nonverbally to all people through nature, conscience, and history. This is referred to as general or natural revelation, and the Bible strongly affirms it. But knowledge of natural revelation of God must never be considered independent of Scripture, because the Bible shows that, left to his own thinking, man will corrupt the revelation of God in nature. Even the Christian needs the guidance of Scripture to properly assess God’s revelation of himself in nature. John Calvin (1509–1564) graphically portrayed this last point, comparing the Scriptures to “spectacles” that give people a clear manifestation of the true God:

Just as old or bleary-eyed men and those with weak vision, if you thrust before them a most beautiful volume, even if they recognize it to be some sort of writing, yet can scarcely construe two words, but with the aid of spectacles will begin to read distinctly; so Scripture, gathering up the otherwise confused knowledge of God in our minds, having dispersed our dullness, clearly shows us the true God.

Therefore, the so-called “natural proofs” for the existence of God cannot be allowed to stand as products of human observation and reason apart from Scripture’s assessment of them. When we look at these “natural proofs,” we must discern whether they do indeed “prove” the God of the Bible. And then we need to discern whether they have any use.


Considered in and of themselves, the “natural proofs” for the existence of God do not prove the existence of the God of the Bible. In fact, they do not even prove the existence of any god. Christians should expect that these “proofs” fail to prove the true God because at least some of them were derived from pagan philosophers such as Plato (ca. 428–348 BC) and Aristotle (ca. 384–322 BC).

The Ontological Argument. The ontological argument for the existence of God states that God’s existence is proved by man’s thought that God exists as the perfect being. In other words, if man can think that God exists as a perfect being, then this God must exist, since for him not to exist would make him not a perfect being. It should be a caution to Christians that the Greek philosopher Plato held a form of this argument, though he concluded that it pointed to many personal “forms,” not to a single God. Plato held that man’s concepts of perfect things cannot be derived from things in this imperfect world, so these concepts derive from real things in the transcendent “world of forms.”

The classic Christian form of the ontological argument was put forth by Anselm of Canterbury (1033–1109) in his works Monologion and Proslogion. He argued that we can think of something absolutely perfect (“something than which nothing greater can be thought”). But if it does not exist, then it is not absolutely perfect since existence must be an aspect of perfection. In that case, we can think of something even greater—something that exists not only in our thoughts but also in reality. So Anselm concluded that an absolutely perfect thing must necessarily exist, and that is God.

One should be warned by the fact that nonevangelical thinkers have also held a form of this argument, including René Descartes (1596–1650), Baruch Spinoza (1632–1677), Gottfried Wilhelm von Leibniz (1646–1716), George Hegel (1770–1831), and Charles Hartshorne (1897–2000). The ontological argument did not lead them to the God of the Bible.

The Cosmological Argument. Another “natural proof” is the argument from the created realm to an Ultimate Cause for it all. It was captured in Thomas Aquinas’s (1225–1274) “first way,” “second way,” and “third way” of proving the existence of God. As Aquinas taught, there cannot be an infinite sequence of causes, so there must be an unmoved mover (the “first way”), a “first cause” (the “second way”), an original and absolutely necessary being sufficient to produce all created things (the “third way”). And that “first cause” is God.

However, caution must be noted in that the Muslim philosopher Al-Ghazali (1058–1111) used a form of the cosmological argument to argue for the existence of Allah. And the cosmological argument was later held by the nonevangelical Enlightenment philosopher Gottfried Wilhelm von Leibniz.

The Teleological Argument. Another “natural proof” is the teleological argument, the argument from design. This argument (Aquinas’s “fifth way”) holds that the complex order, design, purpose, and intelligence in the universe is the result of the work of an intelligent, purposeful designer, who is God. This argument has also been held by non-Christians: Plato, Aristotle, and Immanuel Kant (1724–1804). Therefore, this argument also does not necessarily point people to the true God.

The Moral Argument. The moral argument proposes that the ethical phenomena in man (conscience, reward and punishment, moral values, and the fear of death and punishment) imply a moral being who created and maintains the moral order in the world. A form of the moral argument is visible in Aquinas’s “fourth way,” which argues from the gradation of beings to an ultimately perfect being, who is their cause. Aquinas believed that this ultimate being must be the cause of all the perfections that characterize other beings, whether goodness, truth, or something else. And this ultimate being “we call God.” Note, though, that the Enlightenment philosopher Immanuel Kant also asserted a form of the moral argument, and he denied both the Trinity and the incarnation.

Other Arguments. Two other arguments merit brief mention. First, the “universality of religion” argument states that because most people in the world believe in some kind of personal power, and because most of these either worship a personal deity or deities or word their devotions in personal terms, then this universality of religion points to something in the nature of man. The most reasonable explanation for the origin of this aspect of human nature is that a higher power has made man as a religious being. Second, the “progress of humanity” argument contends that the apparent progress in human civilization throughout history indicates that man is on the way to fulfilling the plan of a wise and omnipotent world ruler, who is God.

Response to the “Natural Proofs.” All the “natural proofs” represent a theology based on man’s reason and do not necessarily lead to the true God. These “natural proofs” are exercises in building theology “from below,” of measuring God by human thinking. As hinted by the cautions above, these arguments do not necessarily point logically to the triune God of the Bible since many who have used them did not believe in the true God. By themselves, these “natural proofs” are not proofs of the existence of any god without first presupposing what a god is.

Here are some general criticisms of these so-called “proofs”:

       1.    None of these arguments necessitate only one God, and none of them necessitate the God of the Bible. These arguments can point just as easily to multiple beings.

       2.    None of these arguments necessarily point to something that is perfectly good or unchangeable, since the world is marked by so much evil and change.

       3.    None of these arguments necessarily point to that which is perfect, since perfection might transcend what man can think, since human ideas exist necessarily only in man and since not all people have a common concept of perfection.

       4.    None of these arguments prove that an infinite sequence of causes is inherently impossible, and none of these arguments necessitate that any original cause or designer is a “god,” unless one has first presupposed a definition of “god.”


The above response concerning the inadequacy of the “natural proofs” for the existence of God should warn against seeing them as having inherent value as humanly derived evidences that God exists. As humanly crafted arguments, they are useless; they do not prove the triune God of Scripture. Still, they can be useful. When derived from the Bible, they are forms of biblical truth and can be used by the Holy Spirit to convict people of their truthfulness.

In considering the usefulness of these arguments for God’s existence, one must first ask several questions:

       1.    Are any of these arguments true without imported presuppositions?

       2.    What presuppositions make each argument “work”?

       3.    Is their reasoning so cogent that one should expect any of these arguments to persuade an otherwise rational person? Does their reasoning necessitate that an otherwise rational person who rejects them is acting irrationally?

       4.    Can these arguments be useful in evangelical ministry? If so, how?

As “natural proofs”—that is, as arguments based on man’s observation of and reasoning about nature—these “proofs” do not logically prove the existence of the true God. Louis Berkhof writes that “none of them can be said to carry absolute conviction.” Of course, this fact means not that the existence of God is contrary to logic but rather that these arguments fail to demonstrate the existence of God in a compelling way to those who suppress the truth in unrighteousness (Rom. 1:18). Instead, they must be considered in concert with biblical presuppositions—namely, that the God of the Bible exists, that he is one, and that he is sovereignly powerful over all creation. While God has given sufficient evidence of his own existence in creation and conscience, the unregenerate suppress the truth of general revelation in unrighteousness (Rom. 1:18–21). Therefore, all people have within them the awareness that God exists, but in their depravity they suppress and corrupt the knowledge of God revealed in nature.

Because man’s depravity is total, the curse of sin reaches even to man’s mind, so that his thinking is futile, his understanding is darkened, and he walks in ignorance (Eph. 4:17–18). As a result, the natural man’s faculty of reasoning is corrupted by sin. For this reason, believers cannot and should not rely merely upon the “natural proofs” as evidence for the existence of the true God.

In fact, a significantly more radical change must take place for sinful man to come to a true knowledge of the triune God of Scripture. As those whose minds have been blinded to the glory of God revealed in Christ (2 Cor. 4:4), unbelievers do not need more evidence, whether logical or empirical; rather, they need new eyes to properly evaluate the sufficient evidence they already have. They need to experience the miracle of regeneration, in which God quickens the unbelieving heart by shining into it the light of the knowledge of his glory (2 Cor. 4:6). This happens only by the proclamation of the gospel that Jesus Christ is Lord (2 Cor. 4:5).

In the final analysis, then, only the gift of saving faith, imparted by the Holy Spirit through the Word of God (Rom. 10:17; James 1:18; 1 Pet. 1:23–25), supplies the basis for the knowledge of God (Heb. 11:1, 6). As Berkhof observes concerning Christians, “Their conviction respecting the existence of God does not depend on them [the ‘natural proofs’], but on a believing acceptance of God’s self-revelation in Scripture.” Christians believe that God exists because God has shone the light of his self-authenticating glory into their hearts through the Word of God.8

Nevertheless, the “natural proofs” do serve valid ministry purposes—when they are seen not as humanly derived proofs but as God-given biblical summaries of natural revelation and testimonies to the existence of the God of the Bible. As Berkhof helpfully explains,

They are important as interpretations of God’s general revelation and as exhibiting the reasonableness of belief in a divine Being. Moreover, they can render some service in meeting the adversary. While they do not prove the existence of God beyond the possibility of doubt, so as to compel assent, they can be so construed as to establish a strong probability and thereby silence many unbelievers.

Bavinck adds, “But though they are weak as proofs, they are strong as testimonies. They do not force the mind of the unbeliever, but they are signs and testimonies which never fail to leave an impression on the soul of any person.” Therefore, the “natural proofs” can instruct and encourage the believer and silence the unbeliever but only when they are drawn from Scripture and so partake of the unity of Scripture. Only then will these arguments function as they are designed: a valid part of proclaiming the gospel as a testimony to the existence of God.

An important model of properly arguing for the existence of God is Paul’s sermon to the Greek philosophers on Mars Hill (Acts 17). It is important to note, first, that Paul did not engage in dialogue but preached a sermon. He said, “For as I passed along and observed the objects of your worship, I found also an altar with this inscription, ‘To the unknown god.’ What therefore you worship as unknown, this I proclaim to you” (Acts 17:23). Paul preached to the philosophers. In so doing, he drew on the Old Testament theology of God and creation and applied it against the false beliefs of Epicureanism, Stoicism, and other philosophies about God, nature, purpose, death, and sin.

For example, Paul proclaimed that God is the transcendent, personal, sovereign Creator by his imperial power: God “made the world and everything in it, being Lord of heaven and earth” (Acts 17:24). This statement reflected Old Testament theology (cf. Gen. 1:1; Ex. 20:11; Isa. 42:5) and directly contradicted the Epicurean view that everything came about by the chance concourse of eternal atoms. Paul’s assertion also stood against the Stoic concept that everything in the world originated from a fatalistic, impersonal, rational principle (the logos).

Also, Paul confronted the Epicureans with the Old Testament truth that the personal, sovereign God exists independently of man-made buildings: God “does not live in temples made by man” (Acts 17:24). Paul did not deny that God could manifest his presence in earthly buildings such as the Old Testament tabernacle and temple, but rather, Paul denied that God needed physical buildings to live in. This statement was also Old Testament truth. In reflecting on the temple that God told Solomon to build, Solomon said to God, “But will God indeed dwell on the earth? Behold, heaven and the highest heaven cannot contain you; how much less this house that I have built!” (1 Kings 8:27). And later, Isaiah delivered a message from God: “Thus says the Lord: ‘Heaven is my throne, and the earth is my footstool; what is the house that you would build for me, and what is the place of my rest?’ ” (Isa. 66:1). Paul’s use of Old Testament theology opposed the Epicurean belief that the gods lived in temples made with human hands.

Paul similarly focused Old Testament theology against the Stoic and Epicurean beliefs about man’s duty to serve the gods properly. The Stoics taught that man should live by impassively accepting and conforming to impersonal fate. They believed that one should live by the principle of apatheia (passionless indifference). The Epicureans taught that man should serve the gods by the principle of atarxia (mental pleasure), which, to them, was a lack of desire for any pleasure. The Stoics and the Epicureans had differing views about what service to the gods should look like, but both systems believed that the gods needed man’s service. Paul did not deny that man should serve God, but he did deny that the true God needed man’s service: “nor is he served by human hands, as though he needed anything” (Acts 17:25). Paul could have also shown that the Old Testament concept of duty to God was a matter of love for God (Deut. 6:4–25). Regardless, Paul clearly preached Old Testament theology. The true, sovereign God needs nothing from man:

I will not accept a bull from your house or goats from your folds. For every beast of the forest is mine, the cattle on a thousand hills. I know all the birds of the hills, and all that moves in the field is mine. If I were hungry, I would not tell you, for the world and its fullness are mine. (Ps. 50:9–12)

Yet another example of Paul using Old Testament theology to challenge the false beliefs of the Epicureans and Stoics is Paul’s preaching that God, as the personal, sovereign Creator, governs the life of man and the world by his providence. He provides to all people what they need to live: “He himself gives to all mankind life and breath and everything” (Acts 17:25). And God has given people their national life with its time and boundaries: “And he made from one man every nation of mankind to live on all the face of the earth, having determined allotted periods and the boundaries of their dwelling place” (Acts 17:26). This message opposed the Epicurean belief that life arose from the blind-chance concourse of atoms and that everything in history has occurred because of man exercising his free will in cooperation with an impersonal nature. And Paul’s preaching was against the Stoic assertions that life was by the impersonal, fatalistic logos principle and that the nations and all things in history ultimately had no distinctions and resulted from impersonal fate. These teachings echoed Old Testament theology. God personally created all things and gave life to all living creatures (Isa. 42:5), and he foreordained the political existence and boundaries of the nations: “When the Most High gave to the nations their inheritance, when he divided mankind, he fixed the borders of the peoples according to the number of the sons of God” (Deut. 32:8).

In proclaiming the gospel based on an Old Testament theology of God and creation, Paul expressed (1) that God is the personal First Cause and designer of all creation, (2) that he is independent of the world but sovereign over it in directing his determined course for it, (3) that all life is from him and depends on him, (4) that he is the source and final Judge of morals, and (5) that he has provided a way for sinners to be spared final judgment through repenting of sin and idolatry. So Paul used aspects of the various “natural proofs,” yet he derived these concepts not from human reason but from God’s self-revelation in the Old Testament. Thus Paul used a quotation from the pagan Greek poet Epimenides (ca. sixth century BC) not as a source of truth but to illustrate to the Aereopagites that their own cultural icons knew the truth even if they denied it (Acts 17:28; cf. Titus 1:12). He proclaimed God’s revelation to refute the false theism of the Greek philosophers, demonstrating that the “natural proofs” for God’s existence must not ultimately appeal to human perception or reason but to God’s own self-revelation in Scripture.

In summary, God exists. He exists as he is revealed by the Bible. The reason one must believe that he exists is because he said that he exists. His existence must not be accepted on the basis of human reason, because that is limited to time and space and has been corrupted by indwelling sin. God has sufficiently revealed himself in the Bible, but he has not revealed himself exhaustively. Man can know only what God has revealed in Scripture about his nature and works. But that is sufficient for people to know him in a personal, saving relationship. One way God has sufficiently and personally revealed himself to man is by describing himself in Scripture by several different names. It is to the names of God that we now turn.[1]

[1] MacArthur, J., & Mayhue, R., eds. (2017). Biblical Doctrine: A Systematic Summary of Bible Truth (pp. 143–154). Crossway.