Why should we let no unwholesome talk come out of our mouths (Ephesians 4:29)?Ephesians 4:29 falls under a body of instructions urging Christians to "walk in a manner worthy of the calling to which you have been called" (Ephesians 4:1). In verse 29 Paul says, "Do not let any unwholesome talk come out of your mouths, but only what is helpful for building others up according to their needs, that it may benefit those who listen" (NIV).
The English Standard Version translates the phrase for "unwholesome talk" as "corrupting talk." The New Living Translation uses "foul or abusive language," highlighting the harmful nature of such communication. Thayer's Greek Lexicon uses words like "rotten," "putrid," "unfit for use," and "worthless" to define the Greek term (https://www.blueletterbible.org/lexicon/g4550/esv/mgnt/0-1/, retrieved 29 June 2023). Merriam-Webster defines unwholesome as "detrimental to physical, mental, or moral well-being" (https://www.merriam-webster.com/dictionary/unwholesome, retrieved 29 June 2023). Any form of unwholesome talk is immoral and can have negative effects physically, spiritually, and mentally.
While some consider only cuss words as unwholesome talk, there are other forms as well, including destructive criticism, lies, insults, slander, and gossip. Unwholesome talk can vary among cultures, but we usually know when we’ve crossed the boundaries.
Paul gives a simple way to test our speech. Rather than allow "corrupting talk" to exude from our mouths, we are to speak "such as is good for building up, as fits the occasion, that it may give grace to those who hear" (Ephesians 4:29). The end goal is edification, and the timing and tone matter.
This message is clear in other portions of Scripture. For example, followers of Christ are called to be salt and light in the earth (Matthew 5:13–16). These symbolic terms define how Christians should interact with the world. Salt adds flavor to a meal and preserves it, while light brightens an environment. We are called to have godly influence, counter moral decay, and glorify God through our good deeds.
Clearly, a Christian cannot effectively be salt and light if unwholesome talk flows out of his or her lips. Unwholesome talk is inconsistent with Christ and His gospel. Although sinless perfection is unattainable on earth, the Spirit is already at work within us (Philippians 2:13). We should align ourselves with His work, and that includes being mindful of our speech.
James provides further biblical instructions on words and speech. He encourages us to be slow to speak and highlights the importance of our words (James 1:19, 26; 3:3–12). Just as salt water and fresh water cannot come from the same spring, our mouth should not utter both wholesome and unwholesome talk.
Another reason to avoid unwholesome talk is the damage it does to our gospel witness. Our conversations should be gracious, respectful, and gentle (Colossians 4:6; 1 Peter 3:15). We should seek to maintain a godly testimony before the watching world, and uttering unwholesome words will only harm our witness for Christ.
Avoiding unwholesome talk does not mean we must always use "nice" or inoffensive words. Jesus rebuked the Pharisees on occasion, using terms like hypocrites and whitewashed tombs (Matthew 23:13–36). Note that Jesus used these words truthfully and within the context of exposing their falsehood, which we are also called to do. Paul does something similar, issuing a stern rebuke in his letter to the Galatians (Galatians 1:6–8; 5:12).
There is a time for rebuke, but, even then, we must be cautious not to indulge in unwholesome talk under the guise of correction. Do not sin while confronting the sins of others.
Overall, we should not let unwholesome talk come out of our mouth because we are followers of Christ, indwelt by God’s Spirit. We are called to be the salt and light of the earth. Our actions—and our words—play a significant role in spreading the gospel.
What does it mean to speak the truth in love (Ephesians 4:15)?
Does the tongue really have the power of life and death?
What does it mean to not conform to the pattern of this world (Romans 12:2)?
What does 'iron sharpens iron' mean?
How can a Christian be an ambassador for Christ?
Truth about the Christian Life