"24 ¶Therefore whosoever heareth these sayings of mine, and doeth them, I will liken him unto a wise man, which built his house upon a rock:
25 And the rain descended, and the floods came, and the winds blew, and beat upon that house; and it fell not: for it was founded upon a rock.
26 And every one that heareth these sayings of mine, and doeth them not, shall be likened unto a foolish man, which built his house upon the sand:
27 And the rain descended, and the floods came, and the winds blew, and beat upon that house; and it fell: and great was the fall of it."
I would argue that the most important lesson to be learned from this parable is to choose a firm, strong foundation to build our lives upon. When the rains come, the rock foundation remains unmoved while the sand is washed away.
But I think there is another lesson here, besides assuring that we choose a solid foundation .
If building on a rock represents centering our lives on the One, sure foundation - Jesus Christ - then what does building on the sand represent?
Instead of being built on one thing, those who build their lives on the sand have many things as their "top priority". They are not built on one rock, but on thousands or even millions of small "rocks."
These individual grains may be good and even important things - hobbies, careers, education, entertainment, income - but compared to Jesus Christ, they are like a grain of sand compared to a massive rock. And when we try to substitute thousands of good things for the one true Good, we have traded our birthright for a mess of pottage. We have built our lives on things that - as important as they may seem - are insignificant compared to Christ.
There is only one Foundation where we can safely build our lives, and that Rock is big enough for all of us to build upon.