The thought of Proverbs 3:3 is carried step further. No outward charm, but the law of obedience, shall give safety to the traveler, when he sleeps or when he wakes.
Related Commentaries of Proverbs 6:21
Proverbs 6:21-22
21 Bind them continually upon thine heart, and tie them about thy neck.
22 When thou goest, it shall lead thee; when thou sleepest, it shall keep thee; and when thou awakest, it shall talk with thee.