"For as the rain cometh down, and the snow from heaven, and returneth not thither, but watereth the earth, and maketh it bring forth and bud, that it may give seed to the sower, and bread to the eater: So shall my word be that goeth forth out of my mouth: it shall not return unto me void, but it shall accomplish that which I please, and it shall prosper in the thing whereto I sent it" (Isaiah 55:10-11).
In these familiar verses, there is a beautiful anticipation and spiritual application of the so-called "hydrologic cycle" of the science of hydrogeology. The rain and snow fall from the heavens and eventually return there (via the marvelous process of river and ground water run-off to the oceans), then later evaporation by solar radiation and translation inland high in the sky by the world's great wind circuits, finally to fall again as rain and snow on the thirsty land, beginning the cycle once more.
But they do not return until they first have accomplished their work of watering the earth, providing and renewing the world's water and food supplies to maintain its life.
Analogously, God's Word goes forth from heaven via His revealed Scriptures and their distribution and proclamation by His disciples. It does not return void, for it accomplishes God's spiritual work on earth. But it does return, for it is "For ever . . . settled in heaven" (Psalm 119:89).
The fruitful spreading of God's Word is presented in many other Scriptures. For example: "Cast thy bread upon the waters: for thou shalt find it after many days. . . . In the morning sow thy seed, and in the evening withhold not thine hand: for thou knowest not whether shall prosper, either this or that, or whether they both shall be alike good" (Ecclesiastes 11:1,6).
Thus, as we sow and water the seed-which is the Word of God-we have God's divine promise that it will accomplish that which He pleases. HMM