One could assume that the intent of this verse could be paraphrased, "Only a person who hates another would deliberately wound or hurt someone by lies." However, this verse really suggests, upon closer reading, that the very act of saying something negative about another will automatically reinforce this belief.
In explaining this principle of reinforcement, psychologist George Weinberg states, "Every time you act, you add strength to the motivating idea behind what you've done." Weinberg describes graphically how hatred and resentment can be built from scratch:
At a party Ralph makes an offhand remark critical of a certain movie. When he first makes his remark, his attitude toward the movie is actually mild. He may even have liked it on the whole, and his remarks merely to display his cleverness. But he gets a surprise. Instead of just smiling at the gibe, someone at the party contradicts it. Ralph answers back. The other man rebuts again. Ralph attacks another aspect of the movie. The man is unmoved. Ralph tears into the other man's notorious bad taste. Ralph's basic attitude toward the movie has changed. Now he really hates it. At the next party he goes to, almost the first subject he brings up will be the movie, to attack it thoroughly.
As the hatred grows, Ralph's personality and character become sullen and ugly. His own tongue contaminates his very being. James 3:6 reveals, "[The tongue is a] world of wickedness set among our members, contaminating and depraving the whole body" (The Amplified Bible). Verse 8 continues, "It is a restless (undisciplined, irreconcilable) evil, full of deadly poison."