What does Proverbs 26:18 mean?

Prior lessons warned about those who make excuses to avoid accountability (Proverbs 26:13, 16). Verses 18 and 19 depict someone caught in a lie who tries to brush it off as a joke. "Firebrands," sometimes referred to as "fiery darts" (Ephesians 6:16), ignite what they strike. An earlier proverb referred to someone firing arrows without control (Proverbs 26:10). The person who casually lies is throwing destruction around like an insane man launching flaming arrows in every direction. Like a modern person blindly shooting a rifle in a crowd, damage will be done, whether it's intentional or not. Saying "I didn't mean it," after the fact, doesn't remove the damage done.

Lies might come out of carelessness or gossip. They may be inspired by frustration and anger towards another person. In either case, they are dangerous not only for dishonesty, but for a lack of judgment. Scripture warns that we should rein in angry responses, in part to avoid hasty mistakes and slander (Ephesians 4:26; Romans 12:19). Fits of anger indicate the influence of sin nature (Galatians 5:20). The "madman" depicted here is someone lacking sanity and control.