Proverbs 25:3

The heaven. The height of the atmospheric heavens can be fairly well established. The height of the stellar heaven is unknown. New and larger telescopes that penetrate vast distances disclose no limits to the starry heavens. Thus the heaven is unsearchable for height. Each new discovery reveals still higher heights to be searched out.

The earth. As men have been unable to journey far into outer space, so their burrowings into the earth have been restricted to mere surface tunnelings. Probing with sound waves and studying earthquake shocks have yielded valuable information, but the actual knowledge of the substance of the heart of the earth remains much as it was in the days of Solomon.

Unsearchable. As the heavens are unsearchable for height and the earth for depth, so likewise are the hearts of kings impenetrable to their fellow men. Even those human beings who are closest to one another do not really know what is going on in each other’s mind; still less can a subject fathom the mind of the king. Even a courtier who thinks he is able to keep the king’s favor by flattery never knows when he may find that another has taken his place.