When you think of logic, who comes to mind? Probably someone like Sherlock Homes who uses his wit and mind to outsmart his opponents. Maybe you feel this way when you’ve had a conversation with someone with a different belief system or when you’re sharing your faith. It’s as if you’re jockeying back and forth trying to outsmart each other with logic. Well, this can certainly happen, but technically, logic is just the careful and proper use of reason. Logic is important for Christians so we can arrive at truthful beliefs ourselves, but it’s also important in conversations with other people so we can help them arrive at truth in a loving manner.
Let me share a story that might help. Some time ago when I was a graduate student studying philosophy I had a memorable conversation with a professor from an Ivy League school. He said to me, “I think it’s great you’re studying philosophy as a Christian. Maybe you’d want to study Buddhist philosophy because all religions are true.”
Now that struck me as very odd. I thought for a minute, “How can all religions be true when they contradict on such fundamental teachings about God, the afterlife, and how you get salvation.” So I simply asked him a question. I asked, “How can all religions be true, namely Islam and Christianity? Muslims say if you believe Jesus is God, you’ve committed the sin of Shirk, and you’re certainly going to Hell. I say Christians say that that you can’t get to Heaven unless you believe Jesus is God. How could both of these be true?”
He kind of fumbled around a little bit, and we kept talking. Eventually, he looked at me and said, “Here’s the deal. Religion aside, what is really true is cultural relativism. Therefore, you should be tolerant.”
Now stop and think about this. Use your mind and your logic to analyze this claim. He said he believed in cultural relativism which says morality and truth depend upon the culture. But then he turned to me and said, therefore, because morality is relative, I should be tolerant. Now, do you see the inconsistency? If morality is relative, he can’t turn to me and say I ought to be tolerant because he’s appealing to tolerant as if it’s a universal truth claim that everybody should follow. On the flip side, if he says that everybody should be tolerant, then he doesn’t actually believe morality is relative because he’s appealing the universal principle or standard of tolerance.
Friends, people hold a lot of different views about God, religion, and morality. One important thing to do is to listen to their views and draw it out. What we often see is that their views will lead to inconsistency and sometimes even to logical absurdity.
For example in Matthew 22:41- 45[1] Jesus uses the known logical principle of reductio ad absurdum. Now that sounds really fancy, but essentially what it means is reducing a position to absurdity. In this passage in Matthew Jesus is having a conversation with the Pharisees and he asks them, “Who do you think the Messiah is? Is the Messiah the son of David?”
And they say, “Yes, the Messiah is the son of David.” And what Jesus said was to draw out their view, to show that it leads to absurdity. Now how does he do this? He quotes from Psalm 110:1[2] in which David, who wrote that Psalm, says that Messiah is his Lord. And Jesus said, “Wait a minute. You just said that the Messiah is the son of David, but now we have David calling the Messiah Lord. How can that be?” Jesus is saying that if you think the Messiah is merely the son of David, then that leads to absurdity. But, rather, it’s more reasonable to conclude that, yes, the Messiah is the son of David, but He’s more than human. He actually is LORD as David himself says in Psalm 110:1. In my conversation with the Ivy League professor, I was trying to show that he held two views in contradiction that when drawn to their logical conclusion led to absurdity. This is exactly what Jesus was doing with the Pharisees.
This is why the Apostle Paul in Ephesians 4:14-15 says, “We are not to be like children in terms of our thinking tossed to and fro by different waves of doctrine.” Rather, we are to grow up and be mature in the way we think. Paul also says in this passage that we are to speak truth in love. In other words, we are called to speak truth. We can’t compromise truth. We don’t speak truth just to win arguments. We don’t speak truth just to prove people wrong. We do it because we know that it is only truth that can set men free.
And keep in mind that your conversations will not always go as smoothly as it seemed to go with mine with the Ivy League professor. In fact more often than not, after I have a conversation with somebody I will step away and go, “Oh, I should have said this. Oh, next time I’ll say that.” Learning to love God with our minds and learning to use logic is a lifelong process.
You’re learning some powerful stuff about truth and defending the faith in this entire study that we’re going through. It’s easy to think, “I’m going to write this down. I’m going to go online. I’m going to go in person to my parents, my friends, and other nonbelievers and win some arguments. If that’s what your thinking, you are missing the point. The point of this is not to go out and win arguments. The point of this is to, number one, know the truth for ourselves and then second to speak that truth in love—to use reason, to use logic to love people. That way as people draw closer to you, learn more about your faith, they will find something genuine and real that is not easily put out.
41 While the Pharisees were gathered together, Jesus asked them, 42 saying, “What do you think about the Christ? Whose Son is He?”
They said to Him, “The Son of David.”
43 He said to them, “How then does David in the Spirit call Him ‘Lord,’ saying:
44 ‘The Lord said to my Lord,
“Sit at My right hand,
Till I make Your enemies Your footstool” ’?
“Sit at My right hand,
Till I make Your enemies Your footstool” ’?
45 If David then calls Him ‘Lord,’ how is He his Son?”
The Lord said to my Lord,
“Sit at My right hand,
Till I make Your enemies Your footstool.”
“Sit at My right hand,
Till I make Your enemies Your footstool.”
