The ending of the Sermon on the Mount is classic! Jesus spent extended time teaching His disciples (and the crowds) on the nature of the Kingdom. He taught them that they could do nothing to enter the Kingdom. He taught them their only hope was to be broken and come in as a beggar. He expanded the law for them, saying that what really matters is the heart behind the action. It does not matter whether you have never murdered, but have you ever been angry? That is just as bad in God's eyes. When He gets to the end, He drives home the entire sermon with a story.
Yes, that's right, He ended His sermon with a good illustration. The story is that of the wise and foolish builder who both built the same house. They were both hit by the same storm. But there were quite different results. Why did Jesus tell this story at the end of the Sermon on the Mount? He is asking one last time: "what are you going to do with my words?" This is His final appeal, are you going to obey and listen and be different based upon what He just said, or not?
Jesus is saying that the only appropriate response to His words is obedience! I have studied this passage many times in the past. I have read it, taught it, been taught it, and have sang songs about it. And that is probably the most dangerous part of this text--familiarity. My experience has often been that those who approach texts of Scripture with an "I already know that" sort of mentality, they will miss what the Lord is trying to teach them. But if we come with open hearts, wanting and ready for the Lord to teach, we just might be surprised at how He changes us.
For this story of the wise and foolish builder, I think it can be boiled down to this: one guy planned and worked hard and one guy was lazy. The wise man worked really hard because he knew that the dry season wouldn't last forever and eventually he would have to face the storms. The foolish man just wanted to finish building as quickly as he could so that he could just enjoy the house.
The only difference between these two guys is the foundation. And according to the context, the foundation is obedience to the words of Jesus! The wise man was not comfortable with shallow responses to the words of Jesus. He cared so much about it that he worked really hard to ensure that it would endure till the end. Why is it difficult? Because the message of Jesus is difficult. It is free, but it is difficult. Even in this sermon, Jesus' message is "plucking out your eye" or "cutting off your hand." Does that seem easy? No, of course not. But that is why it is going to take some careful planning and hard work to obey the words of Jesus.
But don't misunderstand what I am saying. Ultimately, the hard work is found in trusting Jesus and responding in faith to all that He says. Are you willing to trust Him and obey Him that when He tells you to do something and it makes no earthly sense at all, that He will take care of you? It is responding to His message by faith. Will you respond to Jesus by faith and work hard to apply His message to your life? Then you are the wise man who built his house upon the rock. If not, you are the foolish man!