If you had two minutes to provide a rational defense of Christianity, what would you say?
This is part one of a four-part series of essays attempting to answer that question. These essays will by no means exhaust the possible answers, but they will help to equip us as Christians to give “a reason for the hope that is in us” (1 Pet. 3:15). Below, I want to look at what I consider to be one of the most important arguments for the truth of Christianity. It was put forward in its most popular form by C.S. Lewis and is known as the ‘Lord, Liar, Lunatic’ argument, or the Trilemma.
The argument
Here is the argument in Lewis’ own words from his book Mere Christianity:
I am trying here to prevent anyone saying the really foolish thing that people often say about Him: I’m ready to accept Jesus as a great moral teacher, but I don’t accept his claim to be God. That is the one thing we must not say. A man who was merely a man and said the sort of things Jesus said would not be a great moral teacher. He would either be a lunatic – on the level with the man who says he is a poached egg – or else he would be the Devil of Hell. You must make your choice. Either this man was, and is, the Son of God, or else a madman or something worse. You can shut him up for a fool, you can spit at him and kill him as a demon or you can fall at his feet and call him Lord and God, but let us not come with any patronising nonsense about his being a great human teacher. He has not left that open to us. He did not intend to…. Now it seems to me obvious that He was neither a lunatic nor a fiend: and consequently, however strange or terrifying or unlikely it may seem, I have to accept the view that He was and is God.
This argument is effective because it points people to the very heart of the Christian faith: the person of Jesus himself. The essence of the argument is that we cannot put Jesus off as a ‘good teacher.’ It calls us to actually, honestly engage with the person of Jesus that we find in the Bible and make a decision about his extraordinary claims. However, one major obstacle to any engagement with Jesus is skepticism about the biblical text. Lewis assumed that most of his hearers recognized the biblical texts as generally reliable. Unfortunately, this belief is not shared by many today.
In order to restore the argument’s usefulness, we must therefore make a case that the gospels provide a generally reliable portrait of the historical figure of Jesus of Nazareth. To do so, let’s focus on four major areas: reliability of transmission, non-Christian documentary evidence, archaeology, and internal evidence.
The reliability of the gospels
First, people will sometimes claim that we can’t trust the gospels because we only have copies of copies of copies. While it is true that we only 
have copies of the original New Testament documents, this is the case for almost every book written before the invention of the printing press in the 15th century. However, the New Testament is by far the best attested ancient document that we possess (see the figure to the right). In comparison, the second-best attested ancient document is Homer’s Iliad, for which we have only 1,700 manuscripts compared to over 5,000 manuscripts and fragments of the New Testament. The New Testament fares just as well using other metrics like the time between the original writing of the documents and the oldest extant fragment (500 years for the Iliad versus 50 years for the New Testament) or complete manuscript (1600 years for the Iliad versus 300 years for the New Testament). If we apply the same standard to the NT that we apply to any other ancient writing, we would have to conclude that the NT accurately preserves the contents of the original documents.
Second, we can show that the New Testament accounts of Jesus mesh well with what we know of Jesus from other sources. Even if we were to consider only the work of non-Christian authors like Josephus, Pliny the Younger and Tacitus, we would know the following facts: a) that there was a Jewish man named Jesus who lived in 1st century Judea, b) he was called the Christ or Messiah by his followers, c) he did some kind of miraculous deeds and was accused of leading the Jewish people astray, d) he was brought to the authorities and was crucified under Pontius Pilate, e) the movement he founded was first checked by his execution, but later returned and spread as far as Rome, f) the early Christians chanted to Jesus ‘as if to a God’ but refused to worship other gods, even on pain of death. In other words, we would have a complete outline of Jesus’ life entirely from non-Christian authors.
Third, archeology has offered substantial confirmation of the New Testament. There is no question that the New Testament takes place in the real historical world of the 1st century Roman empire. Cities like Jerusalem, Antioch, Rome, Athens, and Corinth have been thoroughly excavated. But archaeology also confirms extremely small details mentioned in the NT. For instance, we’ve found the pool at Bethesda mentioned in John 5:1-15, the pool of Siloam mentioned in John 9:1-7, the synagogue at Capernaum where Jesus preached (Luke 4:31-36), the ossuary of the high priest Caiaphas (Matt. 26:57-67), a 1st century house from the village of Nazareth where Jesus grew up, inscriptions naming Pontius Pilate prefect of Judea (Luke 3:1-2), Gallio proconsul of Achaia (Acts 18:12-17), and proconsul Serguis Paulus of Cyprus (Acts 13:6-13). The fact that archaeology confirms not only the general setting of the gospels, but very incidental details of the narrative, serves to substantiate the reliability of the biblical authors.
Finally, there are numerous pieces of evidence internal to the gospels themselves that give them credibility. For instance, the authors’ familiarity 
with local terminology, 1st century politics, Palestinian/Mediterranean geography all support their claim to be either eyewitnesses or the careful recorders of eyewitness testimony. Let me elaborate here on one particular piece of evidence which I consider to be very powerful. Just in the last few decades, archaeologists have compiled a database of hundreds of proper names drawn from ossuaries, or bone-boxes, of Jews born between 300B.C. and 200 A.D. in Palestine. From this data, we can determine the relative frequencies of the names and compare them to Jewish names mentioned in the gospels and Acts. Not only do we find that the most popular New Testament names match the most popular names found on the ossuaries, we even find that the percentages roughly agree (see the table above). Given that this data consists of over a hundred names scattered over five different books, it is very unlikely to be the result of coincidence. The best explanation is that the writers preserved the actual names of historical individuals described in the gospels.
With so much evidence of the authors’ meticulous attention to detail and corroboration by archaeology and non-Christian authors, it becomes clear that the gospels can be trusted to provide us with a generally reliable portrait of the historical words and actions of Jesus of Nazareth. But therein lies the problem. Imagine you were accosted today by a man who demanded that you love him more than your father and mother, wife and children, brothers and sisters, or even your own life, who claimed to be the only way to God, who claimed that at the end of time he would judge all of humanity. You would dismiss him as an evil megalomaniac. But Jesus made all of these claims multiple times, throughout his ministry. Moreover, we could consider other people who claimed to be God throughout history: Juanita Peraza, Jim Jones, Sathya Sai Baba. In no other case are we inclined to label these individuals as anything other than dangerous charlatans or lunatics, nor have these individuals had even remotely the impact of Jesus. The Trilemma is just as pertinent and pressing today as it was when C.S. Lewis originally presented it. We can still use it to urge people to seriously consider Jesus’ claim on their lives: Will we accept him as our Lord and Savior? Or will we reject Him?
Potential pitfalls
Finally, let me point out a few pitfalls that are worth avoiding.
First, this argument does not rely on biblical inerrancy or any doctrine of inspiration. Often, conversations about Jesus can turn into long and extremely tedious discussions of apparent biblical contradictions. While it may be helpful to answer such questions, always try to turn the focus back to Jesus himself. The Trilemma does not require us to accept that the Bible is the word of God, which skeptics will be unwilling to do. Instead, it only asks us to treat the gospels as generally reliable works of history.
Second, try not to get caught up in “hot button issues.” While we should not deliberately avoid all controversial subjects, these can often be smokescreens that allow skeptics to avoid the central issue of Jesus’ lordship. While we should present what we believe the Bible teaches with gentleness and charity, it is always helpful to ask the question: “If Jesus isn’t God, then why does it matter what the Bible teaches?” Jesus’ identity should be the focus of the discussion.
Third, don’t forget the gospel. When we point people to Jesus, we forget that they will often still think of him primarily as a moral exemplar rather than as a rescuer. We need to constantly remind others and ourselves that Jesus came not just to teach, but to rescue us from our sin, to free us from our bondage, and to reconcile us to a God who loves us deeply. No matter how prepared we are with thoughtful arguments, our main message always needs to be the good news that God was reconciling the world to himself in Christ, not counting men’s sins against them.
Further resources:
Why Believe? Atheism and Christianity in dialogue – an example of how this argument could be presented in a public discussion
Lectures by Dr. Tim McGrew – over ten hours of lectures on the historicity of the New Testament, delivered by Dr. Tim McGrew, a philosophy professor at Eastern Michigan
The Case for Christ by Lee Strobel – a very accessible but comprehensive treatment of numerous issues surrounding Jesus’ life, death, and Resurrection
Neil Shenvi - Apologetics 