What does Proverbs 25:18 mean?

"Bearing false witness" refers specifically to lying in a formal setting, such as a court case. Scripture considers this a heinous offense since it involves dishonesty and an attack on an innocent person (Exodus 20:16). Other Scriptures repeat God's condemnation of false witnesses (Proverbs 6:16–19; 19:5; 21:28). Lying about a person is sinful enough. To lie during an investigation or trial can cause irreparable harm to the victim. Giving false testimony against someone is as much an attack as hitting them with a weapon. Dishonest statements can ruin a neighbor's life, perhaps destroy his livelihood, hurt his family, and damage his reputation beyond repair.

Many people believe lies without bothering to investigate them further (Proverbs 17:4; 1 John 4:1). The psalmists knew this, as well as the habit of some to bear false testimony. One psalm prays, "Deliver me, O LORD, from lying lips, from a deceitful tongue" (Psalm 120:2). Ephesians 4:25 appeals to believers to renounce lies: "Therefore, having put away falsehood, let each one of you speak the truth with his neighbor, for we are members one of another."