God simply SPOKE creation into existence. God's words have ultimate power and authority. Since we are created in the image of God, it stands to reason that our words also carry power. Obviously, our words are not on the same level as God’s, but they are powerful nonetheless. 

SPOKEN WORDS HAVE POWER!
Spoken words can have a powerful effect on others, for good….or for evil.

"Death and life are in the power of the tongue, and he who loves it will eat its fruits" 
-Proverbs 18:22