Why should we New Testament Christians bother to read and study God’s Old Testament law? And, if we don’t have to obey it in order to be saved, why should we try to put its principles into practice in our lives? Today’s passage gives us a couple of good reasons.

First, although we are saved by grace alone through faith alone in Christ alone, apart from works of the Law (Romans 3:28), putting the principles of the Law into practice is still a good way to live a long and prosperous life (Deuteronomy 4:1). After all, loving and serving God keeps us from all the selfishness and perversion that is involved with so much idolatry. Moreover, loving and serving others is the best way to build trust among people, and such trust is one of the most important hallmarks of any successful society.

Yes, any honest student of history will recognize that cultures that have had the most gospel influence tend to be the most successful by any objective measure. How else can we explain that Christian Europe in general and the Reformed, Protestant part of Europe in particular did so well in spreading its ideas about science and government all over the globe? Just so, Moses points out in Deuteronomy 4:6 that even the unbelieving nations all around God’s people would be able to see the wisdom in living according to God’s Law.

But the most important reason to study and apply the principles of God’s law to our modern life is because it reveals God’s perspectives, God’s preferences, and God’s values to us. As Deuteronomy 4:7 points out, it was because God agreed to live among His people that He gave His law to them. Just so, the best way we can demonstrate our close relationship with God is to live the way He would have us to live, allowing His law to teach us how to love Him with all our heart, soul, mind, and strength, and how to love our neighbors as ourselves.

Deuteronomy 4:1-8 (NASB)

“And now, O Israel, listen to the statutes and the judgments which I am teaching you to perform, in order that you may live and go in and take possession of the land which the LORD, the God of your fathers, is giving you.
2 “You shall not add to the word which I am commanding you, nor take away from it, that you may keep the commandments of the LORD your God which I command you.
3 “Your eyes have seen what the LORD has done in the case of Baal-peor, for all the men who followed Baal-peor, the LORD your God has destroyed them from among you.
4 “But you who held fast to the LORD your God are alive today, every one of you.
5 “See, I have taught you statutes and judgments just as the LORD my God commanded me, that you should do thus in the land where you are entering to possess it.
6 “So keep and do them, for that is your wisdom and your understanding in the sight of the peoples who will hear all these statutes and say, ‘Surely this great nation is a wise and understanding people.’
7 “For what great nation is there that has a god so near to it as is the LORD our God whenever we call on Him?
8 “Or what great nation is there that has statutes and judgments as righteous as this whole law which I am setting before you today?