What does Proverbs 6:28 mean?

Firewalking is a trick where someone takes several barefoot steps across a bed of embers. This has been practiced by many cultures as a ritual but is also done in the modern world as a stunt, a thrill, or even a team-building exercise by businesses. Since coals don't actually conduct heat well, a person can usually take several gentle steps on the coals without massive damage. However, this "trick" is just that: it requires controlled conditions, and even then, those who participate in it usually receive minor burns or blisters.

Rather than disproving Solomon's rhetorical question, firewalking proves the accuracy of this proverb. Even when the situation is tightly controlled, it's risky. Sooner or later, everyone who does it gets burned, at least a little. In the context of adultery, Scripture compares illicit sex to playing with fire (Proverbs 6:27). There are natural consequences one must expect when they take such risks.

Samson learned firsthand that the sin of adultery exacts a heavy toll. When he honored his Nazarite vows, he triumphed over the Philistines as the Spirit of God came upon him, but when he slept in Delilah's lap (Judges 16:16–19) and she cut off his hair, he lost his ability to defeat the Philistines. He thought he could jump up and defeat the Philistines, but he didn't realize the Lord had left him (Judges 16:20). The Philistines overpowered Samson, gouged out his eyes, took him to Gaza in shackles, and made him grind in the prison's mill (Judges 16:21). Later they made a spectacle out of him during a feast to their pagan god Dagon (Judges 16:23–25). Samson's adulterous affair with Delilah led to his weakness, defeat, blindness, and humiliation. While the consequences for most adulterers aren't as dramatic as that, sexual sin always leads to some kind of earthly consequence.