What does Proverbs 13:15 mean?

This verse applauds those who have good sense or good understanding. As defined in the book of Proverbs, those with understanding follow God's truth (Proverbs 1:7). They walk in the light of God's Word that is a lamp to their feet and a light for their path (Psalm 119:105). This godly path keeps them from many of the natural consequences of sin (Proverbs 9:7–12; 11:7; 13:14). A "treacherous" person is one who is unfaithful, rejecting the wisdom of their own Creator (Proverbs 13:1).

Those who seek righteousness (Matthew 7:7–8) will find it in Jesus Christ (John 14:6). Seekers of truth follow Jesus (John 10:4) and reject the way of darkness. Consequently, they enjoy God's favor. This may not always translate to earthly wealth and prosperity (John 16:33), but it guarantees eternal life and reward (John 3:16–18). In general, those who act with wisdom and goodness gain a positive reputation in the world (Proverbs 22:1).

The treacherous lead a calloused life in opposition to God. They harden their hearts toward God and incline them toward evil. Thoroughly entrenched in their wicked ways, they refuse correction and remain unrepentant. Jesus wept over unrepentant Jerusalem that had consistently rejected God's prophets. He said, "How often would I have gathered your children together as a hen gathers her brood under her wings, and you were not willing" (Matthew 23:37). He spoke of the judgment Jerusalem would experience for her treacherous ways, "See, your house is left to you desolate" (Matthew 23:38).