John Gill's Bible Commentary Ver. 9. For they [shall be] an ornament of grace unto thy head , etc.] The instructions and laws of parents being attended unto and obeyed by children, render them more lovely and amiable than any beautiful ornament whatever that can be put upon their heads; and chains about thy neck ; be that unto them as chains of gold are to the neck, beautify and adorn them; so good works, done in obedience to God and parents, are ornaments of great price, and preferable to any outward adorning whatever; (see 1 Timothy 2:9,10 1 Peter 3:3,4). The allusions are unto, and the metaphors taken from, those things which are most pleasing and acceptable to children, as fine top knots and golden chains.
Matthew Henry Commentary
Verses 7-9 - Fools are persons who have no true wisdom, who follow their ow devices, without regard to reason, or reverence for God. Children ar reasonable creatures, and when we tell them what they must do, we mus tell them why. But they are corrupt and wilful, therefore with the instruction there is need of a law. Let Divine truths and commands be to us most honourable; let us value them, and then they shall be so to us.
Original Hebrew כי3588 לוית3880 חן2580 הם1992 לראשׁך7218 וענקים6060 לגרגרתיך׃1621