Don’t use foul or abusive language. Let everything you say be good and helpful, so that your words will be an encouragement to those who hear them.
In the original Greek, this passage speaks of that which is foul, putrid, rotten, decaying, ugly and worthless. Its only use is to be thrown out as quickly as possible. Of course, R-rated language is an obvious target, but this verse speaks to much more than that.
Like I tell my kids, sometimes the most Christ-like thing you can do is shut up! Ephesians 4:29 addresses our careless words… hurtful words… condescending words… harsh words… degrading words… insulting words. In short, if the words you speak to others are not building them up in some way, they are words that should not be spoken.
It has been said that you should think before you act, but think twice before you speak. Careless words do lasting damage and reveal the true sin nature of our hearts (Mth. 12:34). They can hurt or destroy your relationship with your spouse, your children, your friends and your Christian brothers and sisters, not to mention the damage it inflicts on your witness to a watching world.
Get a grip on the fact that some pretty awful things can come out of your mouth, and put Ephesians 4:29 into practice right now. Throw out the rotten fruit and replace it with a bounty of blessings.