3 Final Logical Fallacies to Avoid (and How to Tell When Someone Else is Committing Them)

[This is the final post in the series on Logic and Apologetics]

  1. Begging the Question—assuming a conclusion to be true without proving it. If I am trying to prove that people have lost the ability to distinguish between right and wrong by citing increase numbers of adulterous affairs and abortions, I am assumingadultery and abortion to be wrong, when I should have to arguethat they are wrong. Even though adultery and abortion are wrong, rising incidents of each does not necessarily prove that people have lost the ability to distinguish right and wrong.

How Christians do this:

“I believe the Bible is the Word of God because I just know it to be so.”

“Evolution cannot explain the origin of life on earth, because it is not true.”

How unbelievers do this:

“Science has disproved the existence of God because there is no scientific evidence for God.”

“Jesus cannot be the only way to be reconciled to God, because that would mean all other religions are wrong and most of the world would be condemned.”

  1. Faulty Analogy—making a comparison between two things that are not similar. An analogy allows us to explain one thing by comparison to another. But every analogy breaks down at some point and some things bear no similarity with other things. If I compare the gentleness of a mother with her baby to a nuclear explosion, there is little chance that the analogy will be helpful in any way.

How Christians do this:

“The Trinity is like an apple (or an egg, or water, or a three-leaf clover).”

“If a person is spiritually dead then I won’t bother sharing the gospel with him because dead people don’t hear you when you talk.”

How unbelievers do this:

“Christians used the Bible to support slavery and they were clearly wrong, so when they use the Bible to condemn homosexuality, we can clearly see they are wrongly using the Bible again.”

“Our genetic code is ‘selfish’ and blindly strives to reproduce itself for survival.”

  1. Equivocation—when a word or phrase is used in more than one sense or its meaning changes in the middle of an argument, a dialogue descends into confusion. If I ask my teenager to clean his room and we have two different ideas of what “clean” means, the communication will fail.

How this confusion happens:

Skeptics love to define faith as “belief despite the lack of evidence,” but that is not what Christians mean when they use the word. By “faith” a Christian means trust in God’s revelation. If a skeptic says, “I have evidence and you have faith,” I must correct his erroneous understanding of faith or we will never get anywhere in the discussion.

Similarly, evolutionists often use the word “science” when in fact they believe in scientism(the only things that exist are physical objects and natural, not supernatural, forces guide everything apart from a divine intelligence). If we do not expose the difference, we will find ourselves arguing against science when we have no misgivings about real science.

Hopefully this explanation on logical fallacies has helped you notice some fallacies in your own thinking, as well as building discernment for identifying in the arguments of unbelievers. Skill in detecting logical fallacies takes time and much practice. If you are thinking carefully and critically, however, you will begin to spot fallacies and be able to dismantle them in order to help another person see the truth more clearly.

A Little Note on Logic

Logic is not the final arbiter of all things true, for several reasons. First, flawed and finite people use logic. That means that while logic may help to ensure we arrive at consistency, the premises upon which logical argumentation are built are sometimes disputed. Two rational people can disagree about a premise because even statements of fact are often values-laden. That is, we don’t have a God’s-eye-view of reality without having to interpret what we see. Our own biases, limitations, and errors can creep into our thinking.

Second, logic flows form the character of God. Logic does not stand over God, and therefore some things will not seem logical, even though they are true. 


Christians do not need to resort to logical fallacies, because the Christian faith is the summit of wisdom and rationality. To believe and argue logical fallacies demeans and diminishes the true logic of the gospel. Paul states this clearly in 2 Corinthians 4:3-6 where Jesus is presented as the wisdom of God:

And even if our gospel is veiled, it is veiled to those who are perishing. In their case 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. For what we proclaim is not ourselves, but Jesus Christ as Lord, with ourselves as your servants for Jesus’ sake. For God, who said, “Let light shine out of darkness,” has shone in our hearts to give the light of the knowledge of the glory of Godin the face of Jesus Christ.

Everything pursued by the major cultures of the first century Western world was found in Christ. The Greeks sought the light of wisdom, Jews sought knowledge, and the Romans sought glory, and yet each of these is embodied in the message of Jesus. To seek these things apart from Christ is futile, and to claim to have obtained them apart from Christ requires irrationality and contradiction.

Paul also reminds us that the wisdom of God is wiser than the greatest of “human” wisdom that contradicts it (1 Cor. 1:20-25). This does not mean that unbelievers are not or cannot be brilliant in many areas of human achievement. Some of the brightest scientists, philosophers, engineers, writers, and so on have rejected Christ. It does mean, however, that they can never understand the whyof the knowledge they possess. They can never know the purpose for which they and their expertise exist. They can never understand the infinitely glorious spiritual realities of God’s world until they are transformed by Christ. To make sense of the world they must devise strategies and explanations fraught with logical fallacies. These strategies “work” for them, but they are not the truth. Our prayer is that the Spirit of God will give sight to their blind eyes, abandon their resistance to the gospel built on their fallacies, and see clearly the wisdom and rationality that is Christ.

3 More Logical Fallacies to Avoid (and How to Tell When Someone Else is Committing Them)

red herring[This post continues the series on Logic and Apologetics begun in previous posts]

Logical fallacies are flaws in reasoning that superficially seem to be sound, but upon examination are found to be false. The power of logical fallacies is that even after they have been shown to be flawed, they still retain their power to convince because they are often emotionally satisfying.

  1. Red Herring—an argument that seems to support a person’s position, but in reality, has nothing to do with the question at hand. The name of this fallacy is derived from the practice of dragging a bag of red herring across a scent trail, so dogs would be distracted and lose the scent. When the question at hand is ignored and a related idea is argued instead, a red herring has been committed. This is a difficult fallacy to spot. We must always fight mental confusion and drift to maintain clarity on what the real issue is.

How Christians do this:

“It doesn’t matter that there are so many religions in the world. Christianity is still the truth. You don’t have to eat all the different kinds of cereals at the grocery store to have a favorite.”

“If the Bible is not true, then you must be saying that my grandparents were wasting their time when they read a Bible verse each day of their lives.”

How unbelievers do this:

“How can Christianity be true when there are so many more ways that the church could be helping the homeless?”

“I know God is not real, because I asked him to show himself to me in some way and he didn’t.”

  1. False Dilemma—only two choices are offered when, in fact, there are more options available. Almost always one option is too distasteful to accept, so the listener is forced into a choice he does not want to make.

How Christians do this:

“Ask Jesus to be your Savior right here, right now, regardless of your questions and objections, or you can count on the fact that you will never get into heaven.”

“Either you believe in a literal 24-hour, six-day creation or you cannot become a Christian.”

How unbelievers do this:

“Either you believe in science and reject religion, or you must remain in blind superstition and reject modern science.”

“Either God is not all-powerful, or he is not all-loving. If God were all-loving, he would want to rid the world of evil. If he were all-powerful he would be able to get rid of evil in the world. But there is evil in the world, so either God is not all-powerful or not all-loving.”

  1. Hasty (or Unwarranted) Generalization—a conclusion about everything of a particular kind based on one or a few examples. For example, when we judge all car salesmen based on our experience with one or two of them, we commit hasty generalization. We tend to believe that every individual person, thing, or idea is just like the few we have encountered, heard about, or read about online.

How Christians do this:

 “Atheists are dangerous and immoral people. I know; my neighbor is an atheist, and he has skull tattoos and yells obscenities at his live-in girlfriend.”

“Muslims will never listen to the gospel. Look at how they persecute Christians around the world.”

“Nobody wants to hear the gospel anymore. I have tried witnessing to my coworkers, and they just shut me down and refuse to talk to me about God.”

How unbelievers do this:

“Christians are dangerous to society. That last shooting was carried out by someone who went to church.”

“Churches are all about guilting people into giving their money in exchange for heaven. I visited a church once that took two offerings in one day and the pastor was preaching on money.”

“Fundamentalists are intolerant of other religions.”

In the next post we will conclude this series on logic and apologetics.

3 Logical Fallacies to Avoid (and How to Tell When Someone Else is Committing Them)

Head in Hands[This post continues the short series on Logic and Apologetics posted previously.]

So far, we have looked at the basic structure of logic. Errors in the structure of logical arguments are called formal fallacies. For the sake of brevity, we don’t cover them in this book. Rather we move on to the most common mistakes in informal logic known as logical fallacies. These are flaws in reasoning that superficially seem to be sound, but upon examination are found to be false. The power of logical fallacies is that even after they have been shown to be flawed, they still retain their power to convince because they are often emotionally satisfying.

For example, many Christians believe the following statement to be true, even though it is a fallacy, because it gives them confidence: “Millions of people around the world and throughout history have found peace and hope in Jesus, therefore he must be the way to salvation.” While it is true that becoming a follower of Christ gives peace, that truth does not prove Christianity true. People feel a sense of peace through many means—other religions, no religion, meditation, addictive substances, catching a great wave, or a hike in the woods. This fallacy is called Appeal to Popularity, an argument based on what a large number of people think or believe. It reminds us that nothing is ever true just because it is popular or the majority position.

What follows is a short list of some popular logical fallacies that both believers and unbelievers tend to use in support of or opposition to the Christian faith. I will explain each one,[1]show examples of how both groups argue the fallacy, and then show what is wrong with both. This exercise should help us see that we need to present our reasons for what we believe in true and valid ways. Many of these fallacies have Latin names (post hoc, ad hominem, tu quoque), but for the sake of simplicity I have listed their common English names.

  1. Appeal to Authority—a claim is defended or advanced on the basis of those who believe it. While we may appeal to the arguments of experts in a particular field, just because recognized experts advocate or deny a position does not make it true or false. Nothing is ever true because of who said it, except God.

How Christians do this:

“Einstein believed in a higher being, and he was the smartest man in the 20thcentury, so you should too.”

“Billy Graham spoke to more people than any other evangelist in history, and everywhere he went people were converted, so that shows that the gospel is the truth for every person in the world.”

How unbelievers do this:

“93% of members of the National Academy of Science do not believe in God, so it is not reasonable to believe in God”—Richard Dawkins

“Bart Ehrman is a New York Times Bestselling author, a world-renowned professor at the University of North Carolina, and a graduate of Moody Bible Institute, and he says the manuscripts of the New Testament were corrupted, so it must be true.”

  1. Personal Attack—ignore the argument and criticize its author. Accusing the other person of being unreliable, ignorant, or lacking expertise says nothing about the validity of her argument, but it can have a strong emotional impact on listeners. This fallacy is a form of dishonesty because it distracts from the real issue at hand by focusing on something that has nothing to do with the argument, whether true or false.

How Christians do this:

 “Mormonism cannot be true. Look at the life and crimes of Joseph Smith!”

“How do you knowevolution is the way the world came about? Are youa scientist?

“Bill Nye only has an undergraduate degree in engineering, therefore he doesn’t know anything about biology or cosmology.”

How unbelievers do this:

“Ken Ham only has an undergraduate degree in applied science, so what could he know about advanced science?

“If Christianity was true then Christians would not be such hateful, bigoted, racist people.”

“The disciples were uneducated fisherman, so their ‘eyewitness testimony’ about Jesus’ resurrection was nothing more than hallucination and superstition.”

  1. False Cause—attributing a cause to an event or idea that is not the actual cause. Just because it rains every time you bring Sally with you on a picnic does not mean that Sally causes the rain. Just because your favorite baseball team wins whenever you are in your lucky chair wearing your lucky socks and eating pretzels does not mean that you are causing the wins with your actions.

How Christians do this:

“Attending public school makes teens more likely to walk away from their faith in college.”

“This nation started going downhill when prayer and Bible reading were taken out of schools.”

“The reason crime is on the rise is because people have stopped going to church.”

How unbelievers do this:

“As church attendance falls, violent crime declines; therefore, the faster we get rid of superstitious notions of God, the more peaceful our society will become.”

“Schools that teach children that they are good, and not sinners, have lower rates of failure.”

“Science flies you to the moon; religion flies you into buildings”—Physicist Victor Stenger

It is clear so far that believers and unbelievers alike can commit logical fallacies. In the next post we will look at 3 more logical fallacies that can arise in an apologetic discussion.

[1]Adapted from Stephen S Carey, The Uses and Abuses of Argument (Mayfield Publishing Company, 2000).

Using Logic in Apologetics

invisibleIn a previous post we introduced the basics of logic. Here we see how logic is used in apologetics encounters.

When we apply the science of arguments to apologetics, it is clear that the arguments used against Christianity are often stated informally. The informal statement “I don’t believe in God because I can’t see him” can be written into a formal syllogism such as:

P1: I must see something to believe in it.

P2: I don’t see God.

Conclusion: Therefore, I don’t believe in God.

Notice that Premise 1 (P1) is not stated explicitly in the informal statement, but it is implied. This is where questions are so important in conversations about the gospel. I would not know the reason for someone’s rejection of God unless I asked. Once someone tells me they don’t believe in God because they feel they must see something to believe it, I am able to construct the syllogism above. I can now see his argument clearly and can address it.

In this case the informal statement, “I don’t believe in God because I can’t see him” is an incomplete syllogism. When a syllogism is incomplete, it is called an enthymeme. The challenge of identifying logical problems in an argument is the difficulty of taking the enthymeme as it is stated and filling in the missing terms, so the complete syllogism is clear. This takes time and practice, but eventually you will begin to be able to identify the unstated assumptions of a conversation partner (or yourself!).

In fact, a number of additional premises could be inferred from such a statement, depending on the context of the conversation. For example:

P1: It is not rational to believe in something that cannot be scientifically proven.

P2: I am a rational person.

Conclusion 1: I will not believe in something that cannot be scientifically proven.

P4: There is no way to scientifically prove God.

Conclusion 2: I will not believe in God.

When you begin to see more detail in the unbeliever’s argument, you can break it down and deal with the component parts.

First, we can challenge the unbeliever regarding P1: “Why do you believe that it is not rational to believe in something that cannot be scientifically proven? What about things that all rational people believe in such as the laws of logic and human memory? Where do you get your definition of rationality? What about the limitations of science, such as arriving at wrong conclusions or its inability to explain some things that happen in the natural world?”

Second, we can applaud the unbeliever in her desire to be rational (P2). We can point out that Christianity is deeply concerned about being rational and basing its beliefs on historical events.

Third, as a result of the problems with P1, we can show her that Conclusion 1 she already believes things that cannot be scientifically proven.

Fourth, P4 is not a problem, since we have already established that we can know certain things without proving them scientifically.

Fifth, now that we have challenged the premises that make up this argument, we can challenge the unbeliever to reconsider her rejection of God.

You can perhaps already see how important and powerful logic is in apologetics. Logic is how we see through the objections and challenges to the Christian faith. It is also how we dismantle the arguments of unbelievers and show them the logic of rationality of the gospel of Jesus Christ (2 Cor. 10:3-5). Jesus is the ultimate logic in the universe as John tells us when he describes Jesus as “the Word” in John 1:1-4, 14. The Greek word for “Word” is logos, from which we get the word logic. The Greeks believed that the Logoswas the ultimate rationality in the universe that unified and upheld all that existed. John makes a radical statement when he says that the Logosis both God and became man. That is why it is important for Christians to think and argue logically, because when we do, we reflect the wisdom of Christ.

In the next post we will examine types of arguments in order to help us reason more clearly and with validity in our Christian apologetic.

Basic Logic for Apologetics

logic lightbulb

“Christianity is just not logical!”

A friend of mine who serves in Spain began to encounter this objection when he tried to talk about faith in Jesus Christ. He wrote to me and asked how he could respond. To commit your life to something that is illogical is a serious charge. If Christianity is truly illogical it calls into question how we can expect modern people to believe it. Even more, it raises the question of how we can believe it ourselves. Is the gospel truly against logic?

The answer lies in the nature of logic itself. Logic is one of the powerful tools of apologetics. Logic has the power to expose contradictions in both our thought and the belief systems of unbelievers. Christians are often viewed as illogical and irrational by unbelievers who put great emphasis on rationality, logic, and scientific precision. While it is true that Christians can be illogical and irrational, the Christian faith is neither of these things. The Christian faith is the only belief system that truly reflects the nature of the world and truth as it is. All other belief systems are denials or distortions of the truth.

One of the most powerful ways to defend the Christian faith is to identify and refute logical fallacies in the objections raised against the Christian faith. This requires, first of all, that our own reasoning is marked by true and sound thought. In this chapter we will learn the basics of logical thinking and how logic can help us see through the false beliefs of unbelievers we meet.

The Basics of Logic

Logic is the art and science of reasoning well. More formally, it is “the study of the methods by which the conclusion is proved beyond all doubt.”[1]In other words, logic is what distinguishes between what is not true, what may be true, and what is necessarily true, given the facts. Logic helps us avoid contradiction and irrationality. It also keeps us from allowing incidental or unimportant factors from interfering with our quest for the truth. For example, whether I like something or not, if it is true, I should believe it. Whether I like the person who is telling me a fact, if the fact logically follows from the evidence, I should believe it.

The Elements of Logical Argumentation

To ensure that our thinking is logical, we must understand the basics of logical argumentation. First, the most basic building block of logical thinking is a sentence. A sentence is a complete grammatical thought. Sentences can be short, such as, “Run!” or “Will you?” As long as a subject and verb are present in the proper relationship, you have a sentence.

proposition or statement, on the other hand, is a sentence that affirms or denies something, and can be true or false. “God exists” and “The universe is not eternal” are both propositions that can be used as part of an argument. A syllogismis a kind of logical argument in which one or more propositions are combined to result in a conclusion, or inference. When propositions are used in a syllogism, they are called premises.

An argument consists of at least one syllogism, and often several syllogisms strung together. An argument “is what results when someone advances a claim or series of claims as evidence for the truth of another claim.”[2]What we seek to present in apologetics are arguments that persuade unbelievers toward the truth.

So, to summarize, an argument is a claim for truth and consists of one or more syllogisms, in which the conclusion necessarily arises from the premises.

For example, here is an example of a famous syllogism:

Premise 1: All men are mortal.

Premise 2: Socrates is a man.

Conclusion: Socrates is mortal.

This syllogism consists of two premises that necessarily result in the conclusion (inference). In a syllogism, the truth of the premises is assumed to already be established. If it is true that all men are mortal, and that Socrates is a man, then it necessarily follows that Socrates is mortal.

Even though such words are not used in the example above, sometimes connecting words are used to show more clearly the necessary nature of the conclusion. For example, the conclusion could read, “Therefore, Socrates is mortal,” or “Because all men are mortal, and Socrates is a man, consequently, Socrates is mortal.” Connecting words such as “thus,” “because,” and “therefore” don’t always show up in formal syllogisms like the one above, but we do tend to use them when we speak.

In normal conversations people don’t speak in syllogisms.  They don’t say, “Premise 1: Ice cream costs $4.00. Premise 2: I have $4.00. Conclusion: I have enough money for ice cream.” Rather, we tend to think informally and arrive at such conclusions without working through the logic explicitly in our heads.

In the next post we will look at the value of logic for apologetics.

[1]Gordon Clark, Logic(Trinity, 1988), 1.

[2]Stephen Carey, The Uses and Abuses of Argument: Critical Thinking and Fallacious Reasoning(Mayfield, 2000), 3.

Still More Strategies for Effective Apologetic Encounters

This post concludes the three-part series on Strategies for effective apologetic encounters. To see the first two posts in this series click here and here.

The sixth way to effectively engage unbelievers with the gospel is to identify assertions when arguments are called for. Another common mistake we make when arguing a point is that we don’t actually argue a point! To argue for something is to make logical inferences from two or more truths (as we discuss in the next chapter). Quite often, however, we make assertions rather than present arguments. To assert something is simply to state it without any supporting justification. For example, to say “Christians believe the Bible because they can’t cope with the reality of life and need a crutch on which to rest” is only an assertion if no supporting statements are given that prove that it is true.

Sometimes when we are defending the Christian faith our opponent will make a statement such as the one above. If we don’t recognize it for what it is—a mere assertion—we will often feel helpless to respond. The reason is that an assertion made without any supporting arguments feels like an unimpeachable truth. That is, it comes across with the force of a universally accepted law. But it is not. Until a statement is supported by arguments it is actually nothing more than a wisp of smoke to be waved away.

Here are some examples of assertions that need to be challenged:

  • Science has disproved the Bible
  • All religions are the same
  • There is no proof whatsoever for God
  • Christianity is bad for the world
  • We don’t know what the original manuscripts of the New Testament said

As you can see, these statements seem very intimidating, because they are stated in such a decisive fashion. But they are nothing more than unsupported assertions. We should apply our questions from chapter five whenever anyone tries to get away with such statements.

Seventh, pursue wisely those who wish to avoid conversation on spiritual issues. Sometimes in your efforts to engage people with the gospel, you encounter disinterest or resistance to conversation about spiritual topics. But even if someone tells you directly, “I don’t like to talk about religion” doesn’t mean that the conversation is automatically over. I usually try at least one more strategy if this happens. I will ask, “Oh really? Why?” in the most winsome way possible. That is, sometimes people attempt to shut down the conversation to avoid admitting the reason they don’t want to talk about spiritual issues.

By asking why, you may find that the answer relates to previous bad experiences with Christians, or alternately, a loss that has caused them to question the goodness of God in a broken world. By pressing the issue just a bit you may uncover an openness to further conversation. If the person declines to answer, however, I don’t continue to pursue the conversation. I don’t want to come across as pushy or aggressive. I will simply pray for her and hope to meet again.



Hopefully these strategies provide more clarity and give more tools for effective conversations. Much of it is intuitive. That is, if I keep in mind the command to give an answer with gentleness and respect (1 Pet. 3:15), I will strive to clear objections, so I can talk about Jesus without being annoying. I will listen to what the unbeliever is saying and how she is answering my questions. I will look for ways to incorporate these strategies in order to get to the root of her objections. I will seek to reveal the inconsistencies and irrationality of her worldview and the foundation on which it rests.

Remember, as you are employing these strategies you are tearing down the intellectual and emotional strongholds that the unbeliever has built up over time. These strategies give you various ways to challenge the objections, assumptions, and mistaken notions accumulated over time. Effective engagement requires patience and the insight of the Holy Spirit. Because the Spirit dwells inside us and because we have the divinely revealed Word of God, we can be used by God for the planting and watering of gospel seeds in the lives of those who don’t know Christ.

More Strategies for Effective Apologetic Encounters

drawing businss concept

In the last post we looked at specific ways to take a conversation with an unbeliever to a place of effective engagement about the gospel. In this post we continue to examine those strategies.

The third strategy is to look for implicit bias. Implicit bias is another way of describing subconscious assumptions or unexamined presuppositions. That is, everyone assumes certain things to be true, obvious, and unable to be challenged. Yet, many of these biases cannot be shown to be true, and in fact, can be shown to be false. For example, some people have a reactive bias that makes them want to do the opposite of what someone else is trying to get them to do, or alternately believe the opposite of what someone is telling them. This bias springs from many sources, but one obvious is the dislike of being proven wrong. This is one of the reasons the waywe engage people is so important. If they sense we enjoy proving them to be wrong rather than helping them find truth, we might inflame the reactive bias unnecessarily. The apostle John mentions that Jesus was “full of grace and truth.” What a great reminder that our manner is as important as our message.

Another bias that influences our thinking is known as “sunk cost fallacy.” If a friend has invested time, money, or reputation in a particular belief, he is less likely to admit the belief is wrong. To do so would be to lose all he has invested in that belief. For example, if someone establishes their reputation as a skeptic, becomes known for his skepticism, and has written a book on it, to admit that he is wrong comes at a high price, and his investment in skepticism has to be considered a waste. This is one of the reasons why the Holy Spirit’s conviction is necessary in conversion. Without the Spirit reassuring a person’s heart that loss for the sake of Christ is good, no one would ever be willing to do as Paul did—counting everything but the knowledge of Christ as loss.

Fourth, look for positions that would be embarrassing to maintain. Every worldview besides the Christian faith results in logical conclusions that are an embarrassment in a civilized society. For example, an agnostic acquaintance of mine is an avid participant in state politics. He frequently spends time in the state capitol trying to forbid reference to any religious basis in legislation. In other words, he does not want religion to play a part in any laws that are passed. He is a typical example of a secular humanist.

When I bring up the explicitly Christian foundation of Martin Luther King’s legacy in the Civil Rights movement or William Wilberforce’s battle to end the slave trade in England, however, he becomes uncomfortable. He knows that if he is to be consistent with his principle, he would have to condemn the Christian foundations for these movements. But to do so would be to say that it would have been better to wait for secular activists to resist slavery. This is a claim no one wants to make, because it smacks of racism—a racism that is condemned in Scripture, but not consistently so from a secular humanist standpoint.

Fifth, capitalize on universally held values (justice, opposition to trafficking, abuse, etc.). Many people today who deny the existence of objective morality feel very passionately about certain moral and social issues without realizing the contradiction. They may believe that any sexual choice is perfectly acceptable (as long as there is consent), but become animated about issues of justice, equality, racism, human trafficking, and more (as they should!).

Whenever someone criticizes Christianity for its call to sexual purity, I often ask questions that get to the heart of their morality. The conversation will develop something like this:

Mark: So, you believe that everyone should be able to enjoy whatever sexual practices that make them happy?

Unbeliever: Yes, every person should be able to have their own morality and do as they please.

M: Is that because there is no absolute morality?

U: Yes, that is correct. Morality is relative to each person’s conscience.

M: So, if someone wants to traffic people as sex slaves, they have the right to do that?

U: No! Of course not!

M: But why not? Didn’t you say morality is relative?

U: Yes, but human trafficking is obviously wrong. No one gets to make that choice.

M: But how do you exclude that activity from your rule?

U: Because an act that involves others must be by consent.

M: But where do you get consent? It seems you have pulled that moral rule out of thin air. You have provided no basis for requiring that people consent to what involves them. That makes sense in a Christian worldview where each person is made in the image of God and is afforded dignity as a result. But how do you argue for that in your worldview? And besides, don’t those who traffic other human beings often beat, bully, and threaten them into consent? Don’t they get their slaves to say they are choosing this life when they are questioned by authorities? If we reduce consent to merely verbally-affirmed non-resistance, we have no way to resist someone who is exploiting another person.

You can see in this fictional exchange that there are certain topics related to justice and human dignity that not many people want to oppose publicly because of the near-universal agreement that such things are wrong. It is rather easy to show that these issues only make sense in a Christian worldview.

In the next post we will examine still more strategies for effectively engaging unbelievers with the gospel. To see the first post in this series, click here: Strategies for Effective Apologetic Encounters.

Strategies for Effective Apologetic Encounters


“But, what if the person asks me a question I can’t answer? How do I know where to go with the conversation? What if my mind goes blank?”

The woman who asked these questions had just sat through one of my weekend conferences, and yet felt at a loss as she contemplated sharing the truth of the gospel with her friends and co-workers in the coming week.

Her predicament is a common one. We can learn lots of things about apologetics, feel very confident in the middle of an apologetics conference, and yet seemingly forget everything we have learned the moment we come face-to-face with real people.

Part of the answer is to find reassurance that we know more than we think we do if we have been disciple under sound preaching in our local church, or if we have spent time studying how to give an answer. Very few people have the ability to spontaneously speak on any topic related to belief, unbelief, religion, and the like. Most of us need an occasion or a conversation to jog our memory of what we know.

This is where we need the reminders that Jesus gave his disciples before he ascended to the Father. What reminders?


  • We have the Spirit of truth living in us (John 14:17)
  • The Spirit brings to mind what we have previously learned (John 14:26)
  • The Spirit will declare the truth to us (John 16:13-15)
  • All authority in heaven and earth belongs to Jesus (Matt. 28:18)
  • Jesus is with us at all times (Matt. 28:20)


We need to remember that the Holy Spirit who dwells in believers is the one who will bring to mind what we have forgotten in our short-term memory. The Spirit is the one who will give us words to say when we don’t know on our own. While we should prepare to engage all manners of unbelief, we can never remember everything, nor can we always be knowledgeable about every belief system.

Once we establish the Holy Spirit as the foundation for our apologetic, we can begin to talk about specific tactics that can be used to expose the unbeliever’s presuppositions and worldview. These strategies provide us with multiple ways to challenge unbelief and present the truth of the gospel. When to use which one is entirely dependent on the nature of the encounter with the unbeliever, the extent of the Christian’s knowledge and ability to recognize contradictions and irrationality, and the interest or antagonism of the unbeliever. These tactics can be used by the average Christian to make progress in a gospel conversation with any unbeliever she may encounter.



First, look for erroneous ideas. Erroneous ideas come in all shapes and sizes. Sometimes a person will quote a statistic that you don’t know whether is true or not. Other times someone may make an argument against God using theoretical physics or French philosophy. They may bring up a passage of Scripture that they find objectionable, when you have never studied that passage or heard a good explanation of it. The truth is you can never be so well versed in every area of human inquiry that you will have a specific answer for all the objections that get thrown at you in an apologetic encounter.

When unbelievers include “facts” in their argument that are new or unfamiliar to you, don’t panic. In reality, you don’t know whether these “facts” are really true or not, and if they are real facts, they may be taken out of context or misinterpreted. The Christian must automatically challenge any “fact” used to supposedly discredit the truth of the gospel.

Believers need to be reminded that all wisdom rests in Christ and his gospel, so whatever “facts” are wielded against Christianity are misused or mistaken. The Christian must start with the basic presupposition that this is God’s world and everything in it declares his glory (Psalm 19:1-2) and declares it so clearly that unbelievers are without excuse in God’s sight. So, although I may not know how to answer the objection raised, I know that there is an answer.

So, what should we do if someone argues an idea with which we are unfamiliar or unsure? As we learned in earlier lessons, we should challenge the “fact.” We can say something like:

  • I’ve never heard that before, but it doesn’t seem right to me. What is the source for your information?
  • I don’t know anything about that topic (or subject, issue, etc.). How exactly does that, if it is true, discredit the Christian faith?
  • I think what you are saying is inaccurate or just plain wrong. I don’t have proof or a strong argument right now, but I wouldn’t base my unbelief on that if I were you. I will find details or arguments and get back to you.
  • I am skeptical of that “fact.” That seems pretty far-fetched or contradicts what we know about real life. Maybe you ought to be more skeptical of your sources than you are.”

These may seem to be direct or even blunt responses, but when we are dealing with ignorance or willful rejection of the truth, sometimes we need to be somewhat forceful with the truth. We dare not let mistaken or erroneous ideas go unchallenged in a discussion, lest we undermine further conversation. For example, if I don’t correct mistaken notions about what the Bible is and how it was written and preserved, I undermine my appeal to the Scriptures later because I will have given the impression that I can’t answer challenges to my primary authority.

Second, look for logical fallacies. To be rational we must be logical. Logic keeps us from descending into irrationality. For example, everyone can recognize the irrationality of the following statement. “The sun rises in the east; therefore, you should buy me a new car today.” The second statement does not logically follow from the first, and the first provides no justification for the second. Logic means that we seek to provide reasons for the beliefs we hold. If our beliefs are not based on sound reasons, then we ought to find sound reasons on which to base them, or conversely, abandon those beliefs.

For the Christian, many of our beliefs are grounded in the revelation of God in his Word. The fact that the Bible says something is justification enough for us to believe it, because of our previous beliefs in its authority, reliability, and self-attestation as God’s revelation. We should always seek to believe only what we have good reasons to believe. That eliminates beliefs based on conspiracy theories, wishful thinking, fear, hatred, and a host of other faulty foundations. We dare not commit logical fallacies ourselves if we are going to critique the fallacies of those who reject the truth of the Christian faith.

Unbelievers often commit logical fallacies in their arguments against the gospel. One common fallacy is the disconnect between the evolutionary, materialist view of life and the supposed obligation to be good and love others. Russian philosopher Vladimir Solovyov summarizes it this way: “Man descended from apes, therefore we must love one another.”[1]Clearly the first claim in no way logically results in the second.

In the next post we will continue to look at strategies for effective apologetic encounters.

[1]Quoted in Charles Taylor, A Secular Age, 596.