Matthew 7:24-27 tells the story of the wise man that built his house on a rock, and the foolish man that built his house on the sand. The upshot is that the foolish man had no foundation, so when the rains came down, his house was washed away. The wise man had a firm foundation, and the storm couldn't wash his house away.
This morning, I was reading the parable of the sower in Luke 8:1-15 (also found in Matthew 13:1-23, Mark 4:1-20). In one of the four scenarios in this text, the seed falls on rocky ground. The problem with the rocky ground is that the seed has nowhere to grow but up, but then it quickly withers because it has no moisture1.
So it got me to thinking: The wise man who built his house on a rock is praised, because his house stands firm. The unfortunate seed that started growing on a rock is doomed, because when the sun comes out it withers. What's the difference between the two?
The wise man that built his house on the rock is contrasted with a foolish man who built his house on the sand. The word for sand only shows up a handful of times in the New Testament, and usually is used in the phrase "numbered as the sand of the sea." But it is also used in Revelation 13:1, when John is in vision on the beach looking out at different beasts that are rising out of the sea. In Revelation, the sea is used to refer to a large number of peoples, languages and tongues (Revelation 17:15). The foolish man who built his house on the sand was building his house in close proximity to a place that the Bible says is "worldly". While there appears to be access to life-giving water, when the storm comes, sandy soil without a rock for a foundation leads to ruin.
In the parable of the sower, the problem with the seed that's planted on the rock is that it lacks soil and moisture. This is contrasted with "the good earth," in the parable, which presumably has both adequate soil and sufficient moisture. When Revelation speaks of the earth, it's a foil to the sea. The earth is where the woman flees to escape the storm that the Dragon spews out at her (Revelation 12:14), and it's also a relatively unpopulated place where a beast arises that is unlike the other four sea-beasts (Revelation 13:11).
As I was looking at this, it dawned on me that there are two extremes. There's one extreme where you live right on the edge of the sea on the sand, and you have no anchor for when the storms come in your life (like the religious liberalism of the Sadducees). The other extreme is religious fundamentalism (like the Pharisees) where you get as far away as possible from the sea, and try to live your life on the top of Half Dome in Yosemite where there is no soil and no moisture. At first, you believe that you're founded on the rock, and so you're 100% good–you cloister yourself out from the world, and do nothing but read your Bible and pray. But in this extreme, you also never let yourself access to water. These people focus too much on the rock, and forget that the one who trusts in the Lord "will be like a tree planted by the water that sends out its roots by the stream. It does not fear when heat comes; its leaves are always green. It has no worries in a year of drought and never fails to bear fruit" (Jeremiah 17:8).
Jesus lived a life that didn't go to either extreme. He constantly was grounding (pun intended) himself in His relationship with the Father in solitude in nature, but would go out to the towns and cities to do ministry, but never staying too long to lose His foundation. His spiritual life was neither dry formalism nor wishy-washy whatever-the-culture-wants-ism.
I imagine this is what is meant when the wise man built his house on the rock. I think that this is also the type of rock that Jesus wants to build his church on (Matthew 16:18). God's church should not be so hard and dry that people who join quickly wither, nor should it be a place where when the rains come down, there is no foundation. But rather, it should be a place of good soil, where it can bring forth some 30-fold, others 60-fold, and still others 100-fold (Mark 4:8).
Only the account in Luke mentions the problem of not having moisture. The other accounts in Matthew and Mark say that it withered because it had no root. ↩