What does Proverbs 6:21 mean?

In this verse Solomon emphasizes how tightly his son should clutch his instructions. Israel's Feast of Unleavened Bread was associated with telling one's son to remember what the Lord did for Israel in rescuing her from Egypt. Exodus 13:9 states: "It shall be to you as a sign on your hand and as a memorial between your eyes, that the law of the LORD may be in your mouth. For with a strong hand the LORD has brought you out of Egypt." Taking this text and Deuteronomy 6:8 literally led to the copying of certain texts of Scripture by the Jews, who enclosed them in leather cases and tied them to the left arm and forehead at the time of prayer.

The point here is not that we must literally wear written words on our bodies. Rather, Solomon's words here impress upon his son the importance of loving and obeying his instructions. Today, we honor these instructions by hiding God's Word in our hearts and obeying it. Scripture, and the teachings of true faith, should be ever-present in our lives and thoughts.