In this final section of the sermon on the mount Jesus gives the last warning to the people and to us today. When he speaks of building your house upon the rock he is talking about your life. And again in this section he is giving us the key to life and living a stable and solid life.
Whenever a builder constructs a house, the first thing they do is to dig a foundation. They dig down until they strike bedrock and build the foundation and structure of the home so that it is anchored on this bedrock. This is to ensure that the building can withstand the forces of nature through wind and rain and so on, and be able to stand firm. If the builder were not to do this and just build the house on the surface of the ground, then movements in the soil caused by the elements would cause it to collapse.
Jesus likens life to this same principle of the building of a house. The key to life is to build your life on the solid foundation of his words and do them. The key is in doing what he says. It is not enough to just hear or read the words of Jesus, but you must then also follow up on them and live your life in accordance with his words. This is akin to building upon the rock. jesus’ words are wisdom, based upon the wisdom of God, and it is His words that will lead us to eternal life in the future as well as a stable and solid life in the here and now. His words provide guidance, insight, knowledge and wisdom about all matters pertaining to this life and the future with God. If you take his words to heart, learn them and apply them in your life, then you will find the pathway to truth and life that exists only through faith in Christ Jesus. This is the solid foundation on the rock of Jesus.
The alternative is like a house not just built on the ground but on sand. If a house built without a foundation on soil will not stand, then how much less if it were built on sand. Sand shifts so readily having no binding properties that it is almost liquid. It takes very little wind or water to move sand and so anything built upon it will simply not stand, but very quickly collapse. There is no anchor on sand and no solid base on which to anchor any kind of a structure.
If you were to hear the words of Jesus and do nothing else, it would be the same. You have nothing to anchor to and hold you fast when the winds and rain of trouble, temptation and ordeal come upon you. What is there to hold onto to anchor you against the days of adversity? This is why when we see disaster strike people in the world they fall apart and are perplexed, not knowing which way to turn. They are without hope in the world and as such are at the mercy of the problems, troubles and issues that befall all in the world. But in Jesus there is hope for he provides guidance in his words that will answer these days of adversity. And in him there is protection.
If you would have life and peace in this world then you need to listen to the words of Jesus and then act upon them. You need to take his words to heart and live by them and they will give you light and life.