Deuteronomy 4:1-2 Now therefore hearken, O Israel, unto the statutes and unto the judgments, which I teach you, for to do them, that ye may live, and go in and possess the land which the Lord God of your fathers giveth you. Ye shall not add unto the word which I command you, neither shall ye diminish ought from it, that ye may keep the commandments of the Lord your God which I command you.
A repeated theme in Deuteronomy is “Lest ye forget.” Keep with you the remembrance of God’s great and gracious salvation, and keep His commandments. Law and Gospel. Listen to the laws Moses teaches and do them. Then you will truly live, and the Kingdom is yours. Jesus said something similar in Matthew 7:24: “Everyone then who hears these words of mine and does them will be like a wise man who built his house on rock.”
Life is so much better when we listen and do. Hearken means both listening and obeying the Word. Not “in one ear….” When we hear the Gospel we do it by believing it. When we hear the Law we do it by repentance and faith in the Gospel. Jesus did it for us and we believe Him. It is a Spirit-worked faith that actually changes behavior. Hearken means believe the Word. Faith is the response; good works (doing the Law) is the result of a heart faith.
Furthermore, our proper response is not to add to or take away from the Word of God. (see also Rev.22:18-19). We don’t make our own rules and we don’t remove words from the Bible. We study the Word faithfully to know precisely what God is saying. We support the true and accurate preaching of Law and Gospel. We hear and believe the sweet Gospel, which has the power to change our lives to live according to the Law.