In discussing his apologetic method, C. S. Lewis once stated that he usually found the aut Deus aut malus homo quite useful in demonstrating the validity of Christ's claims.1 The argument, which is summed up in this Latin phrase ("Either God or a bad man"), points out that, if Christ's claims were false, then he could not have been a good man, since he thought of Himself as God. This "liar, lunatic, or Lord" argument was summarized by Lewis in one of his most widely quoted passages:
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 a 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.2
Elsewhere, C. S. Lewis has stated that if Christ's claims for Himself are not true, then they are "those of a megalomaniac, compared with whom Hitler was the most sane and humble of men." He continued:
There is no half-way house and there is no parallel in other religions. If you had gone to Buddha and asked Him, "Are you the son of Bramah?" he would have said, "My son, you are still in the vale of illusion." If you had gone to Socrates and asked, "Are you Zeus?" he would have laughed at you. If you had gone to Mohammed and asked, "are you Allah?" he would first have rent his clothes and then cut you head off. If you had asked Confucius, "Are you Heaven?", I think he would have probably replied, "Remarks which are not in accordance with nature are in bad taste." The idea of a great moral teacher saying what Christ said is out of the question.3
Benjamin Franklin, who was a Deist who did not believe in the divinity of Christ, wrote in his Resolution on Humility that one should "Imitate Jesus and Socrates." It is interesting that, throughout all of history, Jesus has been considered a model of humility. Yet, if He was not whom He claimed to be, then He was the very opposite of humble. William Lyon Phelps has written:
Either his assumption of authority came from his union with God, or he was the most conceited of human beings. Modesty is one of the finest manly attributes; a man cannot be perfect, cannot even be called very good, who lacks modesty, who takes Himself too seriously. If Jesus were only a man, he lacked one of the cardinal virtues and was marked by a fault peculiarly offensive. But the angels and the shepherds and the wise men who celebrated the first Christmas, they knew who he was. Kneeling before the manger at Bethlehem they worshipped the Divine Saviour.4
1 C. S. Lewis, "Christian Apologetics," in C. S. Lewis, God In the Dock, ed. Walter Hooper (Grand Rapids, Mich.: William B. Eerdmans Publishing Co., 1970), p. 101.
2 C. S. Lewis, Mere Christianity (New York: Macmillan Co., Inc., 1943), pp. 55-56.
3 C. S. Lewis, "What Are We to Make of Jesus Christ?" in C. S. Lewis, God In The Dock, ed. Walter Hooper (Grand Rapids, Mich.: William B. Eerdmans Publishing Co., 1970), pp. 157-158.
4 William Lyon Phelps, Human Nature and the Gospel (New York: Charles Scribner's Sons, 1925), pp. 21-22.