What does the Bible say about the power of words?

from the old testament

• Our spoken words have the power to bring life and death into people’s lives. (Proverbs 18:21)
• Proverbs 10:11 contrasts the words of the godly with the words of the evil: “The mouth of the righteous is a fountain of life, but the mouth of the wicked conceals violence.”
• God's Word, of course, carries ultimate power. We can depend on His promises. Isaiah 55:10-11 says, “For as the rain and the snow come down from heaven and do not return there but water the earth, making it bring forth and sprout, giving seed to the sower and bread to the eater, so shall my word be that goes out from my mouth; it shall not return to me empty, but it shall accomplish that which I purpose, and shall succeed in the thing for which I sent it.”

from the new testament

• When Pharisees accuse Jesus of working miracles on behalf of Satan, Jesus exposes them to be like Satan themselves. He goes on to say, “You brood of vipers! How can you speak good, when you are evil? For out of the abundance of the heart the mouth speaks” (Matthew 12:34). Words often have the power to reveal what is in someone’s heart.
• Jesus is referred to as the Word of God (John 1:1), demonstrating how powerful the Word is.
• When we share the Gospel, we share the powerful gift of God’s salvation (Romans 1:16, 10:13-15). The words of the Gospel are life-changing.
• Christians should represent Christ in our behavior and our words. Paul wrote the the Ephesians, “Let no corrupting talk come out of your mouths, but only such as is good for building up, as fits the occasion, that it may give grace to those who hear” (Ephesians 4:29). The fact that our words can build up others shows how powerful they are.
• Salt is often used metaphorically to represent purity, as when Jesus tells His followers that we must be salt and light to the world (Matthew 5:13-16). This is the sense in which Colossians also uses salt: “Let your speech always be gracious, seasoned with salt, so that you may know how you ought to answer each person” (Colossians 4:6).
• In describing the power and effect of our words, James uses the metaphors of a horse’s bridle, a ship’s rudder, and in verse 5, an uncontrolled fire: “How great a forest is set ablaze by such a small fire!” (James 3:1-12).

implications for today

Words are the bedrock to functional relationships. Through our words, we can communicate love, grace, truth, and forgiveness. We can use our words to build others up, to encourage, to correct, to affirm, and to comfort. Or we can use our words as destructive weapons, speaking lies or malice, manipulating or seeking to put others down. Our words are powerful and should always point people toward Christ.

Those in the heretical Word-of-Faith movement believe that spoken words themselves carry a type of mystical power. But while powerful and a testimony to who we are, words are not magical incantations. We can’t speak things into existence; that is the purview of God alone. Rather, the power of words is in the meaning they convey and the effect they have on the human heart.