Matthew Henry Commentary Proverbs 22:15

"Foolishness is bound up in the heart of a child; [But] the rod of correction shall drive it far from him." — Proverbs 22:15 (ASV)

Sin is foolishness, it is in the heart, there is an inward inclination to sin: children bring it into the world with them; and it clings closely to the soul. We all need to be corrected by our heavenly Father.