What does Proverbs 9:18 mean?

Wisdom, depicted as a noble woman inviting people to a feast, offers life and safety to those who listen to her (Proverbs 9:1–6, 10–12). Her mirror image, Folly, lies to disguise the fact that her invitation (Proverbs 9:13–17) leads to death. The repeated lesson of the book of Proverbs is that true wisdom begins with respect for God (Proverbs 1:7; 15:33; Psalm 111:10; Job 28:28). Those who ignore God are defying the very source of creation (Genesis 1:1) and are setting themselves on a path to absolute destruction (John 3:36). Foolishness has its attractions (Proverbs 7:7–27), but it's not a viable alternative to truth.

This contrast was demonstrated in the very first instance of sin. Apparently, Eve did not believe God's pronouncement that eating the forbidden fruit would incur death, although God had said plainly, "In the day that you eat of it you shall surely die" (Genesis 2:17). She chose to believe Satan's lie: "You will not surely die" (Genesis 3:4). She learned the hard way that God cannot lie (Titus 1:2). Since the days of Adam and Eve sinners have been under the sentence of death (Romans 5:12; 6:23), and will experience eternal death in the lake of fire (Revelation 20:1–15) unless they turn from sin to trust in Jesus as their Savior. John 3:16 states: "For God so loved the world, that he gave his only Son, that whoever believes in him should not perish but have eternal life."