The first C.S. Lewis book I ever read was Mere Christianity. In Mere Christianity, Lewis discusses common elements of the Christian religion such as Christian morals and ethics. Before getting to Christian ethics, however, Lewis provides several arguments that seek to establish the truthfulness of Christian theism. Of these arguments, Lewis’s famous trilemma has stuck with me for over a decade. This argument isn’t usually included in works on apologetics; however, I think the argument is interesting and could be useful in daily life. Essentially, the trilemma is an argument that seeks to show that, based on the things Jesus said and did in the gospels, the only logical belief is that Jesus was indeed the divine Son of God as confessed by Christians.
To establish this conclusion, Lewis employs a simple argument. First, Lewis, who was a literary critic by training, argues that the gospels do not have the characteristics of forged documents. Instead, he says that they read more like history than like mythical accounts. Consequently, he says that when we read the gospels, we should read them as accurate accounts of the life and times of Jesus of Nazareth. In these gospel accounts, it is abundantly clear that Jesus believed he was God.
As I prepare to preach my Palm Sunday sermon, I’ve found yet another place in the gospels in which we can see that Jesus believed he was the divine Son of God. In Matthew 21:1-11, Jesus enters the city of Jerusalem. Christians know this to be Palm Sunday, the day on which Jesus went into Jerusalem to die on the cross and be raised from the dead. A closer reading of this passage shows something interesting.
In Matthew 21:1-3, Jesus gives his disciples some cryptic instructions. He says for them to go into a village—probably Bethphage from verse one—and bring back a donkey on which he will ride into the city. After these instructions, Matthew adds a significant comment. Matthew says that Jesus did this to fulfill a prophecy of the Messiah from Zechariah 9:9. In Zechariah 9, the prophet predicts that Israel’s enemies will be defeated and that Israel will finally have peace. This peace will not be won by Israelite armies, however; instead, a king will come and will enter Jerusalem riding on a donkey. This coming king will win ultimate victory over Israel’s enemies and will usher in an unprecedented era of peace and prosperity. Significantly, when Jesus enters Jerusalem to be crucified, he purposefully evokes the Zechariah 9 prophecy of the coming king. Whatever we think about Jesus, we must admit that on Palm Sunday, Jesus believed he was the one about whom the prophet Zechariah had written. He believed he was the coming king.
Given that Jesus did indeed believe he was God, we have to make a decision. We can either agree with Jesus and confess that he is the very Son of God, or we can disagree with Jesus and say that he was not divine. In his trilemma, Lewis claims that there is no middle ground. With his typical eloquence and passion, Lewis says “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.”
The two possible conclusions lead to two different beliefs. If we confess Jesus is the Son of God, then we should be ardent Christians for the rest of our lives. For, this belief entails that the gospel message is true, and God really did come to earth to redeem humanity. If, however, we deny that Jesus was the Son of God, Lewis says we have to decide what to make of him. Lewis believes we have two different options of what to do with Jesus if we deny his divinity and neither is a good option.
If we deny Jesus’s divinity, Lewis says that we have to believe that Jesus was either a liar or a lunatic. On the one hand, we could say that Jesus acted like he was God when he knew he wasn’t. In this case, Jesus would not only be a liar, but he would be a very bad liar and an infamous cult leader. Remember that Jesus taught people to trust in his name for salvation. He claimed to forgive sins and pardon trespasses. He said not to listen to others who promised eternal life for he alone could save souls. Someone who knew that they were not God and taught such things would be a very bad liar indeed.
On the other hand, we could say that Jesus really believed he was God but that he was honestly mistaken. However, such a mistake is not a small mistake but would be evidence of a serious mental illness. If I believe that I’m the best cook in town, nobody would think I was deranged. They’d likely conclude that I simply have an inflated ego. However, if I really believe that I’m a moon orbiting Jupiter, I probably need serious medical attention. Lewis says that a man who believed he was eternal God would be a lunatic “on a level with the man who says he is a poached egg.”
Lewis’s trilemma says that we have to make a choice. Given that the gospels accurately represent Jesus, we can see that Jesus believed he was God. We have to decide whether we agree with him or not. If we say that Jesus is God, we should confess him as Lord. However, if we decide that Jesus was not divine, will we call him a liar or a lunatic? Neither of these options fits with the erudite, quick-witted teacher who espoused a revolutionary code of ethics. Thus, the only logical conclusion is that Jesus was not a liar, nor was he a lunatic. Instead, Jesus was and is Lord.
Notes & Sources
 C.S. Lewis, God in the Dock, in The Timeless Writings of C.S. Lewis (New York: Inspirational Press, 1970), 406-07.
 David. A. Hagner, Matthew 14-28, vol 33B of Word Biblical Commentary, ed. Bruce M Metzger, David A. Hubbard, and Glenn W. Barker (Dallas: Word Books Publisher, 1995), 593-95.
 C.S. Lewis, Mere Christianity, (New York: HarperOne, 1980), 52.
 Lewis, Mere Christianity, 52.