The Efficacy of God's Word

Isaiah 55:10-11

For just as rain and snow fall from the sky and do not return there, but water the earth, causing it to bud and produce, giving seed to the sower and bread to the eater;

so is my word that goes out from my mouth - it will not return to me unfulfilled; but it will accomplish what I intend, and cause to succeed what I sent it to do."