Why Keep God’s Law?

*The below transcript was generated and formatted by AI and may not accurately represent the recording.

I remember many moons ago, many, many moons ago, I stood up in a church and I was asked to preach and lead the service, and as part of the service I read the law, you know, the Ten Commandments, not thinking I was doing anything necessarily scandalous. And yet after the service, I had an elder come up and inform me that, “We don’t read the law around here because we’re not legalistic. We’ve been saved by grace, and so we don’t need to read the law anymore.”

It’s a certain mood, you might say, or attitude that is surprisingly consistent throughout the Christian church today, an attitude that says the law doesn’t really matter. God loves you just the way you are. And God’s grace is sufficient, and so your obedience doesn’t really matter. It’s not something that is off in a faraway land, but it is a view that is very close to us and threatens to tempt not just the church at large, but we ourselves to imbibe.

But it’s not just in the church, is it? It’s all of society, really. We are slowly shifting into a worldview which says it’s only wrong if you get caught. Now, I mean, we scoff a little bit, except it’s pretty normal. And this is not a new thing. In Papua New Guinea, that was the underlying understanding of every Papua New Guinean before the gospel. My parents would regularly engage with people who would say, “Oh, it’s not wrong because I didn’t get caught.” And they were serious. It’s not wrong unless I get caught. And the place that worldview comes from is a denial of the eternal law of God, that every action is either a morally acceptable right or a moral wrong.

And as this law comes to us through the mouthpiece of Moses, maybe we don’t have that problem. Maybe we love the law. Maybe like the psalmist in Psalm 119, we say, “No, no, no, not me. I rejoice that God’s law is one that finds rich spoil.” I love it. I love hearing the Ten Commandments read. Maybe we’re like Martin Luther, who would pray through the Ten Commandments every day, giving thanks for them, checking his heart, confessing his sin, committing himself for the day ahead. Or like Martin Luther, who would send out men to go and visit every church and every minister and make sure that they were adequately reading and teaching the law. Maybe we’re one of those. Maybe we are committed to the law.

And yet it can be possible for us to have a high view of the law, and yet our focus is “thou shalt not” without truly understanding why. And here’s the problem, brothers and sisters. When all you ever do is stress “thou shalt not” without understanding why, you begin to lose all motivation to keep it. Or to say it differently, we become like the Israelites when they make the golden calf. Do you remember that moment? What happens when Moses disappears? The people rise up and play. Why? Because the lawgiver’s gone. And the reason that happens is because they do not understand the heart of the reason why we obey.

And as Moses introduces the law now, he’s done his historical recounting to introduce his sermon. He’s now beginning to explain the law. He’s beginning to introduce the law before he actually gets to the Ten Commandments, and he does it with this opening exhortation to obedience. And we’re gonna see five reasons tonight, five reasons why we must keep God’s law.

1. We Must Keep God’s Law Because the Lord Commanded It

Verse 1 and 2: “Listen to the statutes and the rules that I am teaching you, and do them, that you may live, and go in and take possession of the land that the Lord, the God of your fathers, is giving you. You shall not add to the word that I command you, nor take from it, that you may keep the commandments of the Lord your God that I command you.” Verse 5: “I have taught you statutes and rules, as the Lord my God commanded me, that you should do them in the land that you are entering to take possession of it.”

We must keep God’s word, simply put, because God said so. Parents, maybe you’ve found this with your children. You tell your children to do something, what’s the most common response you get? “Why?” And sometimes what you will say to them is, “Because I said.” And maybe your children are tempted, and maybe children, you’re tempted to say in response, “But that’s not an answer. That’s not fair. I want a reason why.” One of the most important reasons that we can be given is “the Lord said.” Why? Why is that actually a wonderfully satisfactory answer? Because the Lord is God, and I am not. Just like as a child, it is a sufficient reason when our parent says to us, “Because I said.” Why? Because they’re the parent and I’m the child. I am under their authority. So in one sense, you could say we actually don’t need a reason. Now, God’s gonna give us reasons, but we actually don’t need reasons because one of the underlying reasons is God commanded us to. He who has redeemed us out of Egypt, He who has redeemed us out of sin, He who has purchased us by the blood of Christ, He has ownership of us and He has commanded us and therefore we do it.

I mean, none of us would find it very surprising whatsoever if the King of England turned up and told you to do something. You wouldn’t complain, would you? Why? Well, ’cause he’s the king. And as much or little influence he has over New Zealand, he is still the King of New Zealand. And if the king tells you to do something, you do it. Otherwise, in the older days, you would’ve lost your head. Now, how much more when we are thinking of the Lord of Lords and the King of Kings?

But notice how this law comes to us. For them, Moses says, “The Lord has taught me, and I teach you.” And what Moses is explaining to us here is a very important principle, and that is that the Lord himself, he doesn’t come and speak to us verbally, does he? God doesn’t turn up here today and command us things. What does He do? He sends ministers. He sends prophets in the Old Testament. He sends men who have His commands, who have His message, and He commands us through them. Now, Moses doesn’t turn up and make up his own commands, does he? He doesn’t have the authority to do that any more than I have authority to turn up and make up commands. Our ministers, our elders, our preachers, they cannot make up commands and say, “Well, because I’m a minister, I’m making a command for you as a believer.” No. What can they do? They can say, “Thus saith the Lord. This is what the Lord your God says. You shall not have other gods.” And they may command what the Lord commands.

And this is a great encouragement to us because it reminds us that that which God’s spokesmen faithfully declare is to be received in the same light as though God himself were speaking to us. Do you have that view? You know, there’s a reason why the reformers and the Reformed Church by and large has said that preaching is the preeminent means of grace, meaning it’s the chiefly one. It’s not that the other means of grace aren’t significant. It’s not that the sacraments don’t matter. It’s not that prayer doesn’t matter or reading the Bible doesn’t matter. But what they rightly understood is that biblically speaking, in the act of preaching, God speaks in a way that He is heard and received unlike any other means of grace. And this is why the Reformed Church has always put such great emphasis upon the sermon, and they haven’t allowed it to just become a five-minute pep talk with 38 different chorus hymns. Why? Because when the word of God is preached, I hear God speaking to myself, and so we don’t add or take away. But we listen and we do it because it is God’s word coming to me.

This is why you should come with such anticipation on a Sunday, morning and afternoon. Not just because you’re getting together with some of the finest people in New Zealand, not just because we have wonderful fellowship, not just because we’ve got cute babies around here, not just because we enjoy spending time together, but because you’re gonna hear from the Lord. Do you realize God has spoken to you already once today, and he’s in the middle of speaking to you again? Come with that attitude. Come with expectancy. When someone says to you, “What are you doing on Sunday?” Say, “I’m gonna go hear from God.” That’ll get a conversation started, won’t it? You know, people will often say, “Oh, you believe in God. Has he ever spoken to you?” I love to say, “Yes.” It’s not what they mean, but I love to say, “Yes. Yeah, he has, actually.” They go, “Really? When?” I go, “Just last Sunday. Yeah, I went to church, and while I was there I actually heard God talking to me.” They’re generally disappointed when you explain what you mean, but it’s true, isn’t it? And so we listen and we obey.

2. We’ve Been Blessed in the Past by Doing So

The second reason why we must keep the law is because we’ve been blessed in the past by doing so. We’ve been blessed in the past by doing so. Moses recalls an event, verses three and four. He says, “Your eyes have seen what the Lord did at Baal-peor.” Peor is the place, Baal is the god, okay? “For the Lord your God destroyed from among you all the men who followed the Baal of Peor. But you who held fast to the Lord your God are all alive today.”

Now, you might be asking yourself, “What is the Baal-peor thing? I can’t remember.” Okay, it comes to us in the book of Numbers, chapter 25. This is the incident after you get that really fascinating story with Balaam and the talking donkey. Everyone remembers Balaam and the talking donkey. Great story. Straight after that, the Moabites come up with a secret tactic to attack the Israelites, and it’s one that has proved successful pretty much with every single generation of humanity, and that is the secret enticement of women. Balaam, in fact, we’re told in another passage, basically says to the king, “Look, I can’t curse them, but you’ve got lots of pretty ladies. Send your pretty ladies into town. Tell them to bring their idols.” Easy fix. And sure enough, Israel is led into adultery and into idolatry with the prostitutes of Moab. And God comes in judgment and he kills 24,000 people with a plague, and it’s stopped by the zeal of Phinehas when he takes a spear and stabs it through a Moabite woman and a man who are caught in sin, and the plague is stopped. And now we’re told by Moses all of those ones were destroyed, obviously. Why? Because they disobeyed God. But you, what happened to you? You’re alive. And why are you alive? Because unlike all the others, you held firm to my word.

What’s Moses doing here? He’s reminding them, in the past you have seen that when you have faithfully honored God’s word and kept it, it has gone well for you. But when you have disobeyed, God has disciplined you. You want it to go well for you, so obey God’s word. It’s a little bit like, you remember that moment in Genesis 4 when God comes out to Cain, before Cain kills his brother? And God comes to Cain, and he says to him, “If you do well, will it not go well for you? But if you do not do well, behold, sin is crouching at the door, and it will consume you.” It’s the same type of logic. Moses is saying to us, “In the past you have been blessed for obedience, so obey again and be blessed again.”

Can’t we all recognize this? Can we not all look back at times in our lives when we have sought God and His word and read the word and loved the word and sought to walk in obedience, and we’ve delighted in God, there’s been afflictions, and there’s been difficulties, but we’ve known the blessing of God, we’ve known a rich, fruitful relationship with him and joy in the face of adversities. Cannot we say that? And yet can we not also all recognize there’s been times in our life when we’ve lived in sin, when we’ve given ourselves to corruption. And when we look there, what do we see? We see a wasteland. We see discipline. We see punishment. And we look back with deep regret because we recognize our disobedience led to cursing. And Moses is reminding us of what you might call biblical karma. You’ve probably never heard or thought you’d hear me talk about karma before—biblical karma. “If you honor my word,” the Lord says, “I will be with you.” Are we doing it? It’s a challenge to us to be fueled by our previous experience, to look back and remember what had happened in the past.

3. It Will Be a Blessing to the Nations

The third reason we are to keep God’s law is because it will be a blessing to the nations. This is very striking because we often think of Israel as being a very exclusive group, right? We often think about Israel as being that ethnic minority group who excludes everybody else in their own little land. They kill everybody off, and they’re to shun everybody. And yet Moses says that if you keep God’s law, verses 6 to 8, you go into the Promised Land. You do them. It will be your wisdom, and this is what the people will say: “Surely this great nation is a wise and understanding people.” And then Moses adds, “For what great nation is there that has a god so near to it as the Lord our God is to us, whenever we call upon Him? And what great nation is there that has statutes and rules so righteous as all this law that I set before you today?”

What’s the picture Moses is painting? You go into the Promised Land. As you live in the Promised Land, you keep the law of God. And as you keep the law of God, the surrounding nations, not the ones they’re purging, but the surrounding nations, they’ll look at you, and they’ll say, “I’ve never seen anyone. Well, who are these people? These guys have got great laws. These guys are really smart. This is a wise law. This is good for people. They’re flourishing. What kind of a God must they have that would give them a law like this?” What is this? It’s called being a light and a salt in the world, isn’t it? It’s called being a city set upon a hill, as Jesus says in Matthew 5. I like to call it missional obedience. Not obedience to the mission, but mission by obedience. Peter talks about it in 1 Peter. He says, effectively, you could summarize Peter’s exhortation like this: “I want you to live a holy life. When you live a holy life, you’re going to get persecuted. When you get persecuted, you will still have hope. And then they will ask you, ‘Why do you have hope even though I’m killing you?’ And then you are ready to give a defense.” It’s the exact same thing.

One of the reasons we obey is because in obeying, we bear testimony to the one who gives us commands. We know this with our children, don’t we? Isn’t it a delight, parents, when your children go and spend time with someone else, and your children come back, and the parents say to you, “Your children are so well-behaved. I don’t know, like how do you get your children to tidy up so well and listen so quickly and eat with such manners? You must have a really wonderfully structured home.” Parents have these sorts of discussions, don’t they? When they see a really well, lovely, balanced home, people talk about it and they say, “Well, I mean, maybe you should talk to Mr. and Mrs. So-and-So. Have you seen their children? They really know how to raise children.” And it becomes a witness to all the other families of the quality of parenting. It’s the same with us. We obey because in living in accordance with God’s Word, we bear testimony to the very character of God, and it becomes a light in the darkness in a world so filled with evil and corruption, in a world where people abuse their children, and abuse their spouses, and rip off their work colleagues. In a world where people steal the staplers and the pens and the stamps and everything in work. Your boss is surprised because he trusts you, and he gives you keys immediately because he’s just incredibly amazed that you don’t rip him off like 70% of the rest of the world. And you bear testimony to the quality of your God through your obedience. And so they’ll know you are wise. They’ll know you have a God that is near, and they’ll know that your God’s law is righteous.

There’s a beautiful picture of this in the Book of Zechariah, one of the minor prophets. I’ll just turn to it. Zechariah 8:18–23: And the word of the Lord of hosts came to me, saying, “Thus says the Lord of hosts: The fast of the fourth month and the fast of the fifth and the fast of the seventh and the fast of the tenth shall be to the house of Judah seasons of joy and gladness and cheerful feasts. Therefore love truth and peace. Thus says the Lord of hosts: Peoples shall yet come, even the inhabitants of many cities. The inhabitants of one city shall go to another, saying, ‘Let us go at once to entreat the favor of the Lord and to seek the Lord of hosts; I myself am going.’ Many peoples and strong nations shall come to seek the Lord of hosts in Jerusalem and to entreat the favor of the Lord. Thus says the Lord of hosts: In those days ten men from the nations of every tongue shall take hold of the robe of a Jew, saying, ‘Let us go with you, for we have heard that God is with you.’” Isn’t that a stunning picture? The nations: “We’ve heard you’ve got the Lord. We want the Lord. Take us with you.” You know what? That will never happen when God’s people live in disobedience. If you live in sin, no one will ever do that. Why? Because you look and smell exactly like them. Why would they want your God if you look and act exactly like they do?

4. It Will Be a Blessing to the Generation After Us

The fourth reason we’re given is we must keep God’s law because it will be a blessing to the generation after us. It will be a blessing to the next generation. Verses 9 to 10, we’re told to take care and keep our soul diligently, lest we forget the things that we’ve seen, lest we depart from it with our heart all the days of our life, and we’re commanded to make them known to our children and our children’s children. We’re told to take the law of God and to pass it on to our children. But one of the things we can be so tempted to do is to say to our children, “Do what I say,” you know how it goes, “but not what I do.” We can be tempted to undermine the teaching of God’s word with the pattern of our behavior. We’ve probably all experienced this. Whether it’s as a teenager justifying our behavior, we find one example of a Christian that does it, and then we say, “Oh, I can do it because they do it.” The temptation for us is to think, as parents, we can teach the law of God to our children with word only. But we all know as parents that our children learn much more from our patterns of behavior than they do what comes out of our mouth, right? And so we’re being instructed here by Moses to keep the law of God because when we keep the law of God, our children see it, our children observe it, and it will be a blessing to them. By modeling a true devotion to God in accordance with His will, our children will learn to fear God, and then they will teach it to theirs.

You see, you cannot have generational blessing without generational faithfulness, can you? If we all reject God, we can’t expect that the next generation is gonna love the Lord. That would be daft. And so we’re called here not just to speak, but to teach and live out God’s law, and that will be seen and heard and practiced by our children. And then we will truly see the reality of the blessing of God being poured out from generation to generation. There’s a lovely verse about this in the Book of Genesis. You remember the story of Sodom and Gomorrah? Sodom and Gomorrah, when God destroys the place. Just before God goes and does it, the Lord says of Abraham—He’s not speaking to Abraham. He’s actually speaking to someone else. Don’t ask me who. He’s speaking to someone else, and He says, “Shall we tell Abraham what we’re about to do, seeing that I have commanded him to order his children after my ways? Shall I inform him on the details since I have called him to generational faithfulness?” And that’s what the Lord has done for you and I.

And brothers and sisters, this is not just a mom and dad reality. I hope you know that. Because here’s the problem: I can be the most faithful father, and you can be the most faithful mother, but if you take your children to church and they see everyone else living in sin, what’s gonna happen? They’re gonna reject what you say. And so it’s incumbent upon every single one of us to be living in faithfulness so that when the children come here, having been taught the word of God, having been taught the will of God, they come here and they look around the church and they say, “Oh, I see it. I see it in the elders. I see it in the deacons. I see it in the mothers. I see it in the fathers. I see it in the great-grandparents, the grandparents, the parents, the siblings. I see the law of God being lived out in the midst of God’s people.” And so we’re given reasons. It’s God’s law. He commanded it. It’s been a blessing to us in the past. It will be a blessing to the nations in the future. It will be a blessing from generation to generation.

5. Because of the Grace of God’s Covenant

And then lastly, and most importantly, we are to keep God’s law because of the grace of God’s covenant. Verses 10 through 14, Moses reminds them of the day they went up Mount Horeb and they heard the word of God announcing the Ten Commandments Himself. Very different than what you have right now. The audible voice of the Lord summoned forth from the heavens with fire and thunder and lightning, and then two tablets of stone with the five words on each. And He says to them, “You must obey because God has made covenant with you, because God has saved you.” It’s a little bit like I used to say to my children, “You’re a Hagort. Act like it. This is what I expect of you. Not so that you can become a Hagort, but because you are a Hagort and this is how Hagorts act. So pull yourself together, man.”

See, the ultimate reason we obey God’s law is not because of blessings, it’s not because of authority, it’s because of the blood of the covenant. You see, in Exodus 19, the Lord had entered into a covenant with His people. He had prepared them, blood had been sprinkled, cleansing had taken place, and then the words of the covenant went forth. Then in Exodus 24, they come together again and reconfirm the covenant, and all of this is telling us something. Covenantal people don’t obey so they can be covenantal people. They obey because they are covenantal. They are obedient because they have been purchased by the blood of Christ. Because as the catechism says, “I am not my own, but belong body and soul to my faithful Savior, Jesus Christ.” And so we’re motivated to obey because we’ve been bought with something far more precious than gold or silver. We’ve been won through the victory of the cross, and so we go out and we labor with all of our might for our God.

Brothers and sisters, if you miss this, you’re gonna misunderstand the whole Book of Deuteronomy. If you understand the Book of Deuteronomy as being a book of rules and rules alone, you completely miss the book. It is a covenantal book, first and foremost. It is a book from a God who gave everything to obtain His people, and it comes to you and I with that same firm declaration to a people purchased by Christ Himself. And so when you’re tempted to forsake the law because you’ve lost sight of why, you need to think back to all that Christ has done to purchase you. If my sin cost that much, why would I return to it? If that’s how much my Savior loved me, will I not love Him in return? And what is love, according to Jesus? “If you love me, you will keep my commandments.”

And you know, at the end of the day, brothers and sisters, our patient Father is simply reminding us, like all good dads do, is simply reminding us in the same way He reminded Jesus Christ. You know, you remember the temptation of Jesus Christ as the devil comes to tempt Him? At the end of the day, what is the temptation of the devil? The temptation is to convince Jesus to take a path different than the one His Father has commanded Him. “Make your own bread. Jump down from the temple. Worship me. Take matters into your own hand. Don’t depend upon your Father’s will. Do it your own way. You can skip the painful cross thing. Just worship me and I’ll give you the whole world.” What’s the offer? “Just disobey God and I’ll bless you.” And yet, are we not told in Hebrews 12 that for the joy set before Him, Jesus obeyed. He went to the cross. He was motivated by the reason of the joy of His Father. He set his face towards God by faith and said, “Obedience to God is worth more than everything the devil can give me.”

Brothers and sisters, this is what our Father is doing for us today. He’s gonna call us to many different types of things and we can summarize that as the law of God. But we must lay hold of this plan of God, we must lay hold of this motivation of God to bless us and strengthen us and keep us in the path. Because otherwise, we will grow weary, we will grow cold, and we will lose our way. And so I guess the question for you and I today is not just are we keeping the law—that’s a bit too simplistic—but why are you keeping the law? Because if you answer that question wrongly, it could cost you your life. Because if you answer it wrongly, it could lead you to the point where you no longer keep the law and you reject your God. Or if you answer it wrongly, you could think that you’re earning God’s favor by keeping the law, and thereby lose out on eternal life. So what is your motivation? Is it rooted in the atoning work of Christ and the blessings which He pours out upon you, or is it rooted in something else? Check yourself. Return again and love the Lord by keeping His commandments.