What does Proverbs 9:17 mean?

Solomon is contrasting the life-giving invitation of Wisdom, personified as a woman (Proverbs 9:1–6), with the death-bringing seduction of Folly, also imagined as an inviting woman (Proverbs 9:13–16). Earlier passages in Proverbs made comparisons between adultery and foreign water (Proverbs 5:15–18), and depicted a predatory woman seducing foolish men (Proverbs 7:7–27). This verse points out that sin tempts people by claiming that God is withholding good things from us, so we should defy His commands and enjoy what we want (Genesis 3:1–6). The imagery of "stolen water" and "bread eaten in secret" is meant to evoke the idea of something forbidden or taken through illicit means.

However, what Folly offers is far inferior to what Wisdom promises. Wisdom's invitation included mixed wine and prepared meat (Proverbs 9:2). Somehow, human nature prefers what God has placed off limits to the things He has approved. In the garden of Eden, God told our first parents, "You may surely eat of every tree of the garden, but of the tree of the knowledge of good and evil you shall not eat" (Genesis 2:16–17). Our first parents were not content to limit themselves to God's generous provision; they ate what was forbidden (Genesis 3:6).

The adulterer believes illicit sex is more satisfying than sex between a husband and wife, which God has sanctioned (Genesis 1:28). He also believes his sin will remain secret; however it is not hidden from God's pervasive gaze (Hebrews 4:13). And the ultimate result of sin is not happiness, but death (Proverbs 9:18; Romans 6:23).