The imagery of rock and sand in Matthew 7:24-27 symbolizes stark contrasts between permanence and instability, with petra representing a large, massive cliff or mountain range, while sand represents shifting, changing, transient desert terrains. The rock's qualities we regard as positive while sand's qualities we regard as negative. Paul and David symbolize Jesus as the Rock (I Corinthians 10:4, Psalm 18), permanent, everlasting, and immovable, while the shifting sands symbolize the impermanence of worldly pursuits. As we move toward our annual self-examination for Passover, we realize we have too much sand in our shoes, symbolic of compromising with the world's evil standards, prioritizing badly, becoming neglectful, and letting things slip. While Matthew's focus identified the Rock as Christ, Luke's parallel version (Luke 6:46—the sermon on the plain to the multitudes) focused more on the builder and contractor, digging through the hard, compacted particulate matter (the world's corrupt standards and carnal human nature) down to solid bedrock, indicating that we have some urgent work to remove earth, sand and gravel, enabling us to find the foundation of Christ, which resists wind, flood water and ultimately fire. Building on the Rock is equivalent to building on the commands of Christ rather than the world's pulls. The metaphors Paul uses to get rid of the worldly particulate matter include putting off the old man and putting on the new man, leaving the trash and rubbish behind, growing in grace and knowledge, clearing out the bad to replace with the good. We have all come out of a culture built on sand, full of misunderstanding, alienated from God, full of lewdness, corruption , and deceit. Though we should be dead to these horrible things, we still cling to too many of these behaviors, protecting our secret loyalties residing in our carnal nature.