The Heart of Apologetics

Apologetics is not a set of techniques for winning people to Christ. It is not a set of argumentative templates designed to win debates. It is a willingness to work with God in helping people discover and turn to his glory. We are to “follow Him” by casting our nets out to everyone and pointing them to the greater reality of God and the risen Christ.

Excerpted from Chapter 3 and 6 of Mere Apologetics by Alister McGrath (Grand Rapids, MI: Baker Book House, 2012). Used by permission. All rights to this material are reserved. Material is not to be reproduced, scanned, copied, or distributed in any printed or electronic form without written permission from Baker Publishing Group,

Apologetics is not a set of techniques for winning people to Christ. It is not a set of argumentative templates designed to win debates. It is a willingness to work with God in helping people discover and turn to his glory. As Avery Dulles once noted with some sadness, the apologist is often regarded as an “aggressive, opportunistic person who tries, by fair means or foul, to argue people into joining the church.” 1

It’s easy to see how these stereotypes arise. And it’s equally easy to see how dangerous such attitudes can be. The heart of apologetics is not about mastering and memorizing a set of techniques designed to manipulate arguments to get the desired conclusion. It is about being mastered by the Christian faith so that its ideas, themes, and values are deeply imprinted on our minds and in our hearts.

Far from being a mechanical repetition of ideas, apologetics is about a natural realization of the answers we can provide to people’s questions and concerns, answers that arise from a deep and passionate immersion in the realities of our faith. The best apologetics is done from the standpoint of the rich vision of reality characteristic of the Christian gospel, which gives rise to deeply realistic insights into human nature. What is our problem? What is our need? How can these needs be resolved? In each case, a powerful answer may be given to each question, an answer grounded in the Christian understanding of the nature of things.


To help us set our reflections in a proper context, let us recall one of the earliest recorded events in the Gospel accounts of the ministry of Jesus of Nazareth:

As Jesus passed along the Sea of Galilee, he saw Simon and his brother Andrew casting a net into the sea—for they were fishermen. And Jesus said to them, “Follow me and I will make you fish for people.” And immediately they left their nets and followed him. (Mark 1:16–18)

This is a wonderful narrative, packed full of detail and insight. For example, we note that Jesus called fishermen. Contemporary Jewish literature had much to say about people whose jobs made them virtually incapable of keeping the law of Moses. Two groups often singled out for special (negative) comment were carpenters and fishermen—carpenters because they doubled as undertakers and were handling dead bodies all the time, and fishermen because they had to handle and sort mixed catches of clean and unclean fish. Both groups were incapable of observing the strict Jewish rules about ritual purity, which prohibited contact with anything unclean. Yet Jesus calls precisely such fishermen, who hovered on the fringes of Jewish religious life. It’s a powerful reminder of the way in which the Christian gospel reaches out to everyone—even those whom society regards as powerless or valueless.

That’s an important point. But it’s not the most important thing from an apologetic point of view. Here’s the apologetic question we need to ask: What made Simon and Andrew leave everything and follow Jesus? Does Jesus offer compelling arguments for the existence of God? Does he explain to them that he is the fulfillment of the great prophecies of the Old Testament? No. There is something about him that is compelling. The response of Simon and Andrew was immediate and intuitive. Mark leaves us with the impression of an utterly compelling figure who commands assent by his very presence.

Although this account of the encounter between Jesus of Nazareth and the first disciples by the Sea of Galilee is very familiar, we need to read it with an apologetic agenda in mind. It helps us set apologetics in its proper perspective. It reminds us that argument can be only part of our strategy. In many ways, our task is to lead people to Christ and discovery of the living God. Apologetics does not and cannot convert anyone. But it can point people in the right direction by removing barriers to an encounter with God, or opening a window through which Christ can be seen. Apologetics is about enabling people to grasp the significance of the gospel. It is about pointing, explaining, opening doors, and removing barriers. Yet what converts is not apologetics itself, but the greater reality of God and the risen Christ.

To explain this important point, we may turn to another account of the calling of the first disciples:

Philip found Nathanael and said to him, “We have found him about whom Moses in the law and also the prophets wrote, Jesus son of Joseph from Nazareth.” Nathanael said to him, “Can anything good come out of Nazareth?” Philip said to him, “Come and see.” (John 1:45–46)

Having encountered Jesus of Nazareth, Philip is convinced he is the one he has been hoping for. He then tries to persuade Nathanael that Jesus is the fulfillment of the hopes of Israel. Nathanael is clearly skeptical about this, and raises an objection: Could such a person really come from Nazareth? Yet instead of meeting this objection with reasoned argument, Philip invites Nathanael to meet Jesus of Nazareth and decide for himself.

Now Philip might have answered Nathanael with a detailed argument. Perhaps he might have argued that Jesus’s origins in Nazareth represented the fulfillment of a biblical prophecy. Or perhaps he might have set out the various factors that led him, Andrew, and Peter to follow Jesus of Nazareth and believe him to be the culmination of the hopes of Israel. Yet Philip has learned that encounter is to be preferred to argument. Why argue with Nathanael when there is a more direct and appropriate way of resolving the matter? And so Philip says, “Come and see.”

On meeting Jesus and hearing him, Nathanael comes to his own conclusion: “Rabbi, you are the Son of God! You are the King of Israel!” (John 1:49). We see here the importance of pointing people toward Jesus of Nazareth. We can, like Philip, explain what we find so powerfully compelling and attractive about Jesus. But in the end, the ultimate persuasion comes not from our testimony, but from one’s own encounter with the risen Christ.

The point is important. Apologetics, we are often told, is about persuading people of the truth of the Christian faith. Now there is some truth in that—but it is not the whole truth. There are serious limits to the scope of arguments. You may be able to persuade someone that an idea is correct—but is this going to change his or her life? Philip rightly discerns that Nathanael will be transformed not by an argument, nor even an idea, but by a personal encounter with Jesus. He does not argue for Jesus—he points to Jesus. Is this not a helpful model for Christian witness—pointing people to Jesus, whom we have found to be the fulfillment of human longings and the culmination of our aspirations, thus allowing them to encounter him for themselves, rather than relying on our arguments and explanations?

Yet the story continues, and there are further apologetic points to be made. A few days later, Jesus and his disciples attend a wedding at Cana in Galilee. There, Jesus performs a “sign”—he changes water into wine. The impact of this sign on the disciples is significant. As the Gospel narrative tells us, “Jesus did this, the first of his signs, in Cana of Galilee, and revealed his glory; and his disciples believed in him” (John 2:11). Faith is here seen as the outcome of a revelation of the glory of Christ. This goes far beyond reasoned argument. Faith is the response to the realization of the full majesty, glory, and wonder of Christ. Perhaps the most striking example of this is “Doubting Thomas,” who puts his faith in Christ when he realizes he has indeed been raised from the dead: “My Lord and my God!” (John 20:28).


Even this brief discussion of the nature of apologetics indicates that it has a strongly theological dimension. It may be helpful to explore this in a little more detail before proceeding further.

First, the references in John’s Gospel to faith arising from the revelation of divine glory remind us that conversion is not brought about by human wisdom or reasoning, but is in its deepest sense something that is brought about by God. This is a constant theme in the New Testament. Paul’s preaching at Corinth did not rest on human wisdom, “so that your faith might rest not on human wisdom but on the power of God” (1 Cor. 2:5). Faith is not about a mere change of mind; it is about personal transformation through an encounter with the living God.

Second, the New Testament depicts human nature as being wounded and damaged by sin. We are not capable of seeing things as they really are. “The god of this world has blinded the minds of the unbelievers, to keep them from seeing the light of the gospel of the glory of Christ, who is the image of God” (2 Cor. 4:4). Arguments do not cure blindness, nor does the accumulation of evidence, powerful rhetoric, or a compelling personal testimony. Blindness needs to be healed—and such a healing is something only God is able to do. God alone is able to open the eyes of the blind and enable them to see the realities of life. Apologetics thus depends upon the grace of God and the divine capacity to heal and renew. This is not something we can do. This helps put apologetics in proper perspective!

Third, this theological perspective sets the apologetic task in its proper context. We realize we have an important but limited role to play in bringing people to faith. God is the one who will convert; we have the privilege of bringing people to a point at which God takes over. We point to the source of healing; God heals. We witness to the power of forgiveness; God forgives. We explain how God has changed our lives, transforming them for the better; God enters lives, and changes them. We have a real and privileged part in this process, but are not left on our own. Apologetics is always undertaken in the power and presence of the risen Christ.

An analogy may help make this critically important point clearer. Imagine you had blood poisoning some years ago. Certain symptoms developed, and you realized you were seriously ill. A skilled physician told you what the problem was. And there was a cure: penicillin. The drug was quickly administered, and within days you were on the road to recovery. It’s a very easy scenario to imagine, and you could rewrite it easily to widen its reach.

Here’s the critical question: Did the physician heal you? In one sense, yes. In another, no. The physician told you what was wrong with you, and what needed to be done if you were to be healed. But what actually cured you was penicillin. The physician’s diagnosis told you what the problem was. But in the days before penicillin was discovered, this condition meant only one thing: death. There was nothing that could be done to save you. Identifying the problem would not have been enough to heal you. A cure was needed.

This analogy allows us to get a good sense of how apologetics works, and how we fit into the greater scheme of things. To continue this medical analogy, apologetics is about explaining that human nature is wounded, damaged, broken, and fallen—and that it can be healed by God’s grace. The apologist can use many strategies to explain, communicate, and defend the idea that there is something wrong with human nature. Equally, we can use many strategies to explain, communicate, and defend the fact that there is indeed a cure. But apologetics itself does not heal; it only points to where a cure may be found.

We may provide excellent arguments that such a cure exists. We could provide personal testimonies from people whose lives have been changed by discovering this cure. But in the end, people are healed only by finding and receiving the cure, and allowing it to do its work. We may play a real and important role in helping them to realize they are ill and telling them how they could be cured. Without us, they might not find the cure. But the actual process of healing itself results from the power of penicillin, not from our words.


American poet Edna St. Vincent Millay (1892–1950) spoke of “a meteoric shower of facts” raining from the sky. These facts are like threads that need to be woven into a tapestry, clues that need to be assembled to disclose the big picture. As Millay pointed out, we are overwhelmed with information, but cannot make sense of the “shower of facts” with which we are bombarded. There seems to be “no loom to weave it into fabric.” We need a way of making sense of this shower of information. Christianity gives us a way of bringing order and intelligibility to our many and complex observations of the natural world, human history, and personal experience. It allows us to integrate them, and see them as interconnected aspects of a greater whole.

We want to see the big picture that makes sense of all we observe. More importantly, we want to know where we fit into this great scheme of things. No wonder British philosopher and writer Iris Murdoch (1919–99) spoke of “the calming, whole-making tendencies of human thought,” by which she means the ability of a big picture or “grand narrative” to integrate our vision of reality. The Christian faith is about grasping the big picture, enabling us to see a larger and nobler vision of reality than human reason can disclose.

The world is studded with clues about human nature and identity. Reality is emblazoned with signs pointing to the greater reality of God. We need to connect the dots and see the overall picture. We need to weave the threads together and see what pattern they disclose. These patterns are there to be used by the apologist to help others begin to realize how Christianity has the power to make sense of what we think, see, and experience —and to encourage them to discover Christianity’s deeper power to transform human life.

C.S. Lewis spoke of right and wrong as “clues to the meaning of the universe.” A clue is something that suggests, but does not prove. Clues have a cumulative significance, pointing to a deeper pattern of meaning that gives each of them their true meaning. One clue on its own might be nothing more than suggestive, a straw in the wind. Yet a cluster of clues begins to disclose a comprehensive pattern. Each clue builds on the others, giving them a collective force that transcends their individual importance.

So how can we best make sense of such clues? What can they prove? In a criminal trial, the jury is asked to decide which explanation of the clues makes the most sense of them—whether that of the prosecution or the defense. They are not expected to accept that guilt or innocence has been proved, merely that they believe they can reach a conclusion “beyond reasonable doubt.” Apologetics works in much the same way. No one is going to be able to prove the existence of God, as one might prove that “the whole is greater than the part.” Yet one can consider all the clues that point in this direction and take pleasure in their cumulative force. God’s existence may not be proved, in the hard rationalist sense of the word. Yet it can be affirmed with complete sincerity that belief in God is eminently reasonable and makes more sense of what we see in the world, discern in history, and experience in our lives than its alternatives.


One clue is desire—or a homing instinct for God. Many arguments for the existence of God involve an appeal primarily to reason. Others involve an appeal to experience, finding their plausibility within the human heart as much as in human reason. As Pascal once famously commented, “The heart has its reasons, which reason does not understand.” The best known of these arguments is the “argument from desire.” Although this takes various forms, it is most commonly framed in terms of a deep human awareness of a longing for something that is not possessed but whose attraction is felt. Christian apologists argue that this deep sense of yearning for something transcendent is ultimately grounded in the fact that we are created to fellowship with God, and will not be fulfilled until we do so.

One of the most rigorous theological treatments of this topic is found in the writings of Augustine of Hippo. For Augustine, God has created human beings and placed them at the height of the created order, so that they might fulfill their purposes through relating to God as their creator and savior. Without such a relationship, humanity cannot be what it is meant to be. As Augustine put it in a famous prayer to God: “You have made us for yourself, and our hearts are restless until they find their rest in you.” 2

The two most significant apologetic applications of this approach were developed by Blaise Pascal (1623–62) and C. S. Lewis (1898–1963). Pascal argues that the human experience of emptiness and yearning is a pointer to the true destiny of humanity. It illuminates human nature and discloses our ultimate goal—which, for Pascal, is God.

What else does this longing and helplessness show us, other than that there was once in each person a true happiness, of which all that now remains is the empty print and trace?3

Nothing other than God is able to fill this “abyss”—a profound, God-shaped gap within human nature, implanted by God as a means of drawing people back to him.

This infinite abyss can only be filled with something that is infinite and unchanging—in other words, by God himself. God alone is our true good. 4

Pascal’s idea here is often expressed in terms of a “God-shaped gap” or “God-shaped vacuum” within human nature. Although Pascal did not actually use these phrases, they are a good summary of his approach. Pascal argues that the Christian faith offers a framework that interprets the widespread human experience of “longing and helplessness.” This interpretation has two elements: first, it makes sense of the experience; second, having identified what it is pointing to, it allows this human experience to be transformed.


C. S. Lewis develops a related approach that has an obvious importance for Christian apologetics. 5 Lewis acknowledges the importance of frustrated aspirations for many: “There was something we grasped at, in that first moment of longing, which just fades away in the reality.” So how is this to be interpreted? Lewis notes two possibilities he regards as flawed: first, to assume that this frustration arises from looking in the wrong places; second, to conclude that further searching will only result in repeated disappointment, so any attempt to find something better than the world can offer is a mistake. There is, Lewis argues, a third approach—to recognize that these earthly longings are “only a kind of copy, or echo, or mirage” of our true homeland.

Lewis then develops what some might call an “argument from desire,” which could be formalized as follows:

Every natural desire has a corresponding object, and is satisfied only when this is attained or experienced. There is a natural desire for transcendent fulfillment, which cannot be attained or experienced by or through anything in the present world. This natural desire for transcendent fulfillment can therefore only be fulfilled beyond the present world, in a world toward which the present order of things points. 6

Now this is not really an argument for the existence of God, in the strict sense of the term. For a start, we would need to expand Lewis’s point to include the Christian declaration that God either is, or is an essential condition for, the satisfaction of the natural human desire for transcendent fulfillment. Yet even then, this is not an argument to be understood as a deduction of God’s existence.

Yet Lewis saw this line of thought as demonstrating the correlation of faith with experience, exploring the “empirical adequacy” of the Christian way of seeing reality with what we experience within ourselves. It is not deductive, but—to use Charles Sanders Peirce’s term—abductive (involving logical inference). Lewis clearly believes the Christian faith casts light upon the realities of our subjective experience. Augustine of Hippo wove the central themes of the Christian doctrines of creation and redemption into a prayer: “You have made us for yourself, and our hearts are restless until they find their rest in you.” 7 Lewis reaffirms this notion, and seeks to ground it in the world of human experience, which he believes it illuminates.

Lewis thus contends that Christian apologetics must engage with this fundamental human experience of “longing” for something of ultimate significance. The Christian faith interprets this as a clue toward grasping the true goal of human nature. Just as physical hunger points to a real human need that can be met through food, so this spiritual hunger corresponds to a real need that can be met through God. Lewis argues that most people are aware of a deep sense of longing within them that cannot be satisfied by anything transient or created: “If I find in myself a desire which no experience in this world can satisfy, the most probable explanation is that I was made for another world.” 8

Now this proves nothing. After all, I might have a deep desire to meet a golden unicorn. But that doesn’t mean unicorns—whether golden or not—actually exist. That’s not Lewis’s point. Christianity, he points out, tells us that this sense of longing for God is exactly what we should expect, since we are created to relate to God. It fits in with a Christian way of thinking, thus providing indirect confirmation of its reliability. There is a strong resonance between theory and observation— between the theological framework and the realities of our personal experience.


So how can this approach be developed and applied apologetically? Its essential feature is an appeal to human experience —to the subjective world of feelings, rather than to objective analysis of the natural world. Yet these subjective experiences are important to people, not least because people feel they are deeply significant. Not everyone recognizes this kind of experience when it is described; nevertheless, its presence is sufficiently widespread to act as the basis for an important apologetic strategy. Three points need to be made about this approach.

This approach connects with a shared human experience. It engages with something that resonates with many people, offering an explanation of a feeling that many have had and wondered what it meant. This experience is interpreted. It is not a random or meaningless experience, but something pointing to something that lies beyond it. What some might regard as a pointless phenomenon thus becomes a signpost to significance. The experience is declared to be a gateway to God. Only God can bring about the transformation of human experience. Only God can fill what Pascal called the “abyss” within human nature. This interpretation of human experience is not opportunistic or arbitrary, but rather is rigorously grounded in a theological understanding of human nature and destiny.

This “argument from desire” is not a rigorous, logical “proof ” of God’s existence; it works at a much deeper level. It may lack logical force, but it possesses existential depth. It is about the capacity of the Christian faith to address the depths of human experience—the things that we feel really matter. It builds on the sense of restlessness and dissatisfaction within human nature and shows how this is a clue to our true nature and destiny. As Lewis argued, if nothing in this world is able to satisfy these deep longings and yearnings, maybe we must learn to accept that our true home is in another world. To use an image from Renaissance poet Francis Quarles (1592–1644), our soul is like an iron needle drawn to the magnetic pole of God. God can no more be eliminated from human life than our yearning for justice or our deep desire to make this world a better place. We have a homing instinct precisely because there is a home for us to return to. That’s one of the great themes of the New Testament.

This desire is an important point for reflection on the nature of western society. Political philosopher Charles Taylor concluded his recent extended analysis of the emergence of a “secular age” with an assertion that religion will not and cannot disappear because of the distinctive characteristics of human nature—above all, what French philosopher Chantal Milon-Delsol calls a “desire for eternity.” 9 There is something about human nature that makes us want to reach beyond rational and empirical limits, questing for meaning and significance.

A further point needs to be made here: the Christian idea of humanity bearing the image of God has important implications for the role of the imagination. Both Lewis and Tolkien emphasize how our imaginations open up worlds that reflect hints of our true identity and destiny. Often, we dream of beautiful worlds —not because we want to escape from this world, but because something deep within us causes us to long for this kind of reality. As we shall see in what follows, this also has relevance for Christian apologetics.

Alister McGrath is Professor of Theology, Ministry and Education at King’s College London and President of the Oxford Centre for Christian Apologetics. Mere Apologetics is based upon a foundational lecture course he teaches at the OCCA.

Avery Dulles, A History of Apologetics, 3rd ed. (San Francisco: Ignatius Press, 2005), xix. Augustine of Hippo, Confessions I.i.

1. Blaise Pascal, Pensées (Mineola, NY: Dover Publications, 2003), 113. Ibid

See C.S. Lewis, Mere Christianity (London: Harper Collins, 2002), 134-38.

See also a similar argument in C.S. Lewis, “The Weight of Glory,” Screwtape Proposes a Toast (London: Collins, 1965), 94-110.

For Lewis’s approach, see Peter Kreeft, “C.S. Lewis’s Argument from Desire,” G.K. Chesterton and C.S. Lewis: The Riddle of Joy, ed. Michael H. MacDonald and Andrew A. Tadie (Grand Rapids: Eerdmans, 1989), 249-72.

More generally, see John Haldane, “Philosophy, the Restless Heart, and the Meaning of Theism,” Ratio 19 (2006): 421-40.

Augustine, Confessions I.i.1.

Lewis, Mere Christianity, 136-37.

Charles Taylor, A Secular Age (Cambridge, MA: Harvard University Press, 2007), 530.

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