1. First, Scripture tells us that the ESSENCE of the Mosaic Covenant is the same as the Covenant of Grace: Moses tells Israel in Deuteronomy 7:12, “Then it shall come about, because you listen to these judgments and keep and do them, that the Lord your God will keep with you His covenant and His lovingkindness which He swore to your forefathers.” Notice that Moses is not saying: If you listen to these judgments, then the Lord will keep with you the covenant He is making today with you. Rather, Moses is saying: If you listen to these judgments, the Lord will keep with you the covenant He had made with the patriarchs. God isn't saying: If you embrace the terms of the Mosaic Covenant, I will give you the blessings of the Mosaic Covenant. Rather, He's saying: If you embrace the terms of the Mosaic Covenant, I will give you the blessings of the Abrahamic Covenant. This is because the covenant that God was renewing with Israel at Sinai was the same covenant He had made with Abraham. The Mosaic Covenant was simply a continuation of the Abrahamic Covenant. This is all the more explicit in Deuteronomy 29:10-13, where Moses tells Israel, “You stand today. . .that you may enter into the covenant with the Lord your God. . .in order that He may establish you today as His people and that He may be your God, just as He spoke to you and as He swore to your fathers, to Abraham, Isaac, and Jacob.”2 In other words, what God is doing here at Sinai for Israel under Moses is the very thing He had promised to do in His covenant with Abraham. What God would do for Israel in His covenant with them was the very same thing that He had promised to do for the patriarchs in His covenant with them. So then, if the Abrahamic Covenant belongs to the Covenant of Grace, and the Mosaic Covenant is the same in essence, it follows that it must belong to the Covenant of Grace as well.3
2. Scripture tells us that the PRIVILEGES of the Mosaic Covenant are the same as the Covenant of Grace. The passage from Deuteronomy 29 quoted above doesn't just teach us about the essence of the Mosaic Covenant, but also about the privileges contained in the Mosaic Covenant. We read again: “You stand today. . .that you may enter into the covenant with the Lord your God. . .in order that He may establish you today as His people and that He may be your God. . .” This is God's promise to Israel at Sinai: “I will. . .be your God, and you shall be My people” (Leviticus 26:12). We've shown earlier that this is the very heartbeat of God's promise to His people in the Covenant of Grace.4 God further tells Israel in Exodus 19:5-6 that if they will listen to His voice and keep His covenant, “then you shall be My own possession among all the peoples. . .and you shall be to Me a kingdom of priests and a holy nation.” These are also the same privileges given in the Covenant of Grace, for we read of the very same gospel privileges in 1 Peter 2:9-10, where Peter quotes this same verse, applying it to Gentile believers and telling them: “But you are a chosen race, a royal priesthood, a holy nation, a people for God's own possession. . .” Further, God freely bestows the land of Canaan to His people Israel as an inheritance, which He had previously sworn on oath to give to the patriarchs and their descendants. This was also a gospel privilege, since the land of Canaan was a picture of the eternal inheritance God has sworn to freely give to His people in Christ.5 So then, all the privileges given at Sinai were truly gospel privileges.6
3. The CONTEXT of the Mosaic Covenant is the same as the Covenant of Grace: The Lord begins the Ten Commandments by reminding Israel why it was that they were to obey the Law they were about to receive: “I am the Lord your God, who brought you out of the land of Egypt, out of the house of slavery.” (Exodus 20:2).7 In Israel's slavery in Egypt they were confronted with their desperate need for redemption; but in their deliverance we behold God's gracious provision of redemption. They had been enslaved, but now they were set free through the power of God (Exodus 9:16; Psalm 106:8), having been marked with the blood of the Passover lamb (Exodus 12:22). The Law, then, is only given to Israel in the context of redemption. Israel is not to obey God's Law in order to be set free from their slavery in Egypt—but because they had been set free; they are not to obey God's voice in order to be redeemed—but as those who already had been redeemed. We see the same pattern throughout the Law. Leviticus 11:45 says, “For I am the Lord who brought you up from the land of Egypt to be your God; thus you shall be holy, for I am holy.” Deuteronomy constantly invokes God's redeeming of Israel from Egypt as the grounds and reason for their obedience.8 Over and over again we read in the Law Scriptures such as Deuteronomy 27:9-10, where Moses says to Israel: “This day you have become a people for the Lord your God. You shall therefore obey the Lord your God, and do His commandments. . .” God doesn't give Israel the Law in order that they might become His people; He gives them the Law as those who had become His people. Isn't this exactly how God calls us to obedience in the Covenant of Grace?9 Just like Israel, we were enslaved to our sin (John 8:34); but Christ, our Passover lamb was sacrificed; and through faith in Him we are now set free by the power of God (Romans 1:16). Having been set free, God gives us His Law to obey. But like Israel, we do so, not in order to be redeemed, but rather because we've already been redeemed. So then, Israel was to obey for the same reason we do now in the gospel.
4. The REQUIREMENT of the Mosaic Covenant is the same as the Covenant of Grace: When Jesus was asked what was the greatest commandment, He replied that the whole Law could be condensed into this: “You shall love the Lord your God with all your heart and with all your soul and with all your might.” Our Savior chose to quote Deuteronomy 6:5, but the Law is full of Scriptures like these. We read in Deuteronomy 10:12, “Now, Israel, what does the Lord your God require from you, but to fear the Lord your God, to walk in all His ways and love Him, and to serve the Lord your God with all your heart and with all your soul. . .?” Deuteronomy 11:18 says, “You shall therefore impress these words of mine on your heart and on your soul.” What we see is that the obedience God required of Israel reached far beyond externals to the very depth of their being. The Law was never fulfilled by merely keeping a set of rules; it always goes beyond actions to the deepest longings of our hearts. God was not just commanding Israel to obey Him in a perfect but mechanical, robotic way. He was commanding them to love Him, to belong wholly to Him, to know and cherish and walk with Him, to cling to Him; to to follow Him and serve Him with all their hearts. When Jesus expounded the Law in the gospels, He wasn't teaching anything new; He was merely showing what the Law had required all along. This is why Paul says in Romans 7:14 that “the Law is spiritual”; it requires far more than just external obedience; it extends to our thoughts, motives, and the deepest longings of our hearts.10 So then, what God required of Israel under Moses is what He requires of us still in the Covenant of Grace. This is perhaps most clear in Deuteronomy 10:16, where God commands His people to circumcise their hearts. This shows us that all the obedience God requires in the Law is a gospel obedience. God isn't just commanding Israel to obey Him, but to obey Him in a gospel way. He's not commanding a robotic, legal obedience; He's commanding a true and living evangelical obedience. Not just to obey Him, but to obey Him with hearts that have been circumcised by the gospel. What God required at Sinai was gospel obedience.11
5. The PROVISION of the Mosaic Covenant is the same as the Covenant of Grace: God required Israel to love Him with all their being, but in doing this, He actually required the impossible. Adam's fall has made it impossible for man to love God. Jesus tells us in John 3:19 that all of us are born with hearts that love the darkness rather than the Light. To say that all of us fall short of loving God with all our heart and soul is a massive understatement. As fallen sinners, we're naturally both enslaved to our sin (John 8:34) and in love with our sin (John 8:44). We're not only slaves, but willing slaves. We're neither able nor willing to love God. But as we've learned, God provides all that He asks in the Covenant of Grace. God would provide for all the miserable imperfections of His people through the blood of atonement. Christ was fore-pictured and proclaimed in the sacrifices of Leviticus. The believing Israelite would bring an animal to the tabernacle “to make atonement on his behalf” (Leviticus 1:4). The man would lay his hand on the head of the animal, picturing the truth that his sin was being imputed to the animal on his behalf; then he would slay the animal to symbolize the truth that God's wrath must be satisfied—and yet that it might be borne by a substitute. So then, there was forgiveness in the Mosaic Covenant (Exodus 34:6-7).12 Transgression was atoned for; sins were forgiven. There was grace under Moses because Moses was part of the Covenant of Grace. Of course, the blood of goats and bulls can never take away sins. But they pointed to the One who would. God would one day send to His people the Lamb of God, who would live a life of perfect obedience and submission to the Father and then take upon himself on the cross the punishment that every one of us deserves for our sin.13 Further, we read in Deuteronomy 30:6, “Moreover the Lord your God will circumcise your heart and the heart of your descendants, to love the Lord your God will all your heart and with all your soul, so that you may live.” God wouldn't just atone for the sins of His people; He would also take away their hearts of stone and give them circumcised hearts; radically new hearts. So that the Lord would not only provide forgiveness for His people, but also make them willing and able to love the Lord—not perfectly—but no less truly. So then, the way that God provided for His people at Sinai is no different than how He still does today.
6. The CONTENT of the Mosaic Covenant is the same as the Covenant of Grace: Simply put, the Mosaic Covenant points us to Jesus and the gospel over and over again. Through pictures, promises, and prophecies, we see His fingerprints on every page of His covenant at Sinai. This is why the Savior plainly told the Jews, “if you believed Moses, you would believe Me, for he wrote about Me.” (John 5:46). That's an amazing statement. Here, Jesus himself is giving us His own interpretation of the Mosaic Covenant. And what we learn is that, at the end of the day, the Law of Moses is ultimately about Christ. What did Moses write about? He wrote about Christ. In the same way, the author of Hebrews tells us that all those who were listening to Moses had the “good news” preached to them—the same good news that is preached to us (4:2,6). In other words, it was the gospel that was preached to Israel under Moses. So then, Moses' ministry was actually an evangelical ministry—a gospel ministry. How so? We might give just a few examples here: 1) Moses himself points to the greater Prophet like him who was yet to come, of whom God said: “I will put My words in his mouth, and he shall speak to them all that I command him. . .whoever will not listen to My words which he shall speak in My name, I Myself will require it of him.” (Deuteronomy 18:15-19).14 2) The Passover and sacrifices of atonement point to Jesus, “the Lamb of God who takes away the sin of the world!” (John 1:29), as we've seen. 3) The Tabernacle points us to Jesus, who became flesh “and tabernacled among us” (John 1:14).15 4) The Priesthood points to Jesus, our greater high priest who offered himself once for all and ever lives to intercede for us (Hebrews 7:23-28). 5) The Manna points to Jesus, the true bread that has come down out of heaven to give life to the world (John 6:30-33, 49-51). 6) The bronze serpent points us to Christ, who was lifted up just as the serpent in the wilderness, that “whoever believes will in Him have eternal life.” (John 3:14-15). 7) The Rock that Moses struck in the wilderness points to Jesus, for Paul tells us that Israel was “drinking from a spiritual rock which followed them; and the rock was Christ” (1Cor.10:1-4).16 And whatever else we might find in the Law, Scripture sets forth as shadows of the good things to come (Hebrews 10:1); all serving to point us to Christ and his gospel.17 Christ and His redemption are either pictured or promised on every page of the Law of Moses. The Scriptures themselves testify that ultimately, the ministry of Moses at Sinai was all about Christ. And surely it is no different for us now in the Covenant of Grace.
7. Lastly, the MEANS of benefiting from the Mosaic Covenant is the same as the Covenant of Grace. Everything in the Law pointed to Christ. We see Jesus everywhere. But just like us, Israel was called upon to embrace this message of life in Christ from the heart, by faith. Israel had to respond in faith. This is most evident from one particular passage of Scripture. In Romans 10:5-9, Paul says the following:
5For Moses writes that the man who practices the righteousness which is based on law shall live by that righteousness. 6But the righteousness based on faith speaks as follows: 'Do not say in your heart, “who will ascend into heaven?” (that is, to bring Christ down), 7or “Who will descend into the abyss?” (that is, to bring Christ up from the dead).' 8But what does it say? 'The word is near you, in your mouth and in your heart' — that is, the word of faith which we are preaching, 9that if you confess with your mouth Jesus as lord, and believe in your heart that God raised Him from the dead, you will be saved. . .
Here Paul seems to contrast two ways of life, two ways of righteousness; the righteousness that is based on Law and the righteousness that is based on faith. Later we'll deal in detail with the nature of the contrast, but for now I want us to just notice one thing: the Scripture that Paul here quotes in order to describe the righteousness that is based on faith actually comes from a passage in the Law. Let's say it again. Paul is quoting Deuteronomy 30:11-14, a passage in the Law, to describe the righteousness that is based on faith. Isn't that amazing? Paul here quotes from the Law to teach us about the righteousness that is by faith.18 And the reason is simple: the Law required faith.19 Just as the Law pointed to Christ in so many ways—it also required Israel to put their faith and hope in that Messiah it was so often prefiguring.20
Likewise, Scripture helps us understand that the reason most of the first generation of Israel under Moses never made it into the promised land was not because of a lack of works—but because of a lack of faith. The author of Hebrews had told us that the word which was preached to Israel under Moses in the wilderness was the same “good news” that is preached to us—that is, the gospel (4:2,6). Nevertheless, he goes on, “the word they heard did not profit them, because it was not united by faith in those who heard” (4:2; cf. 3:19). In other words, the very place that Israel went wrong was that they failed to believe in the same gospel that's preached to us. And this isn't something we only learn about in the book of Hebrews; the same truth is recorded in the Old Testament Scriptures themselves. For, when Moses recounts why Israel was made to wander 40 years in the wilderness, he declares to them the reason was: “you did not trust the Lord your God. . .” (Deuteronomy 1:32). This is also echoed in the Psalms. Reflecting on why God entered into judgment with Israel under Moses in the wilderness, the psalmist declares: “Therefore the Lord heard and was full of wrath; and a fire was kindled against Jacob and anger also mounted against Israel, because they did not believe in God and did not trust in His salvation,” (78:21-22), and again, because they “did not believe in His wonderful works (v32). So then, the reason that many under Moses missed out on the blessing was not because of a lack of legal obedience—but rather a lack of faith.21
So then, the question that we would put to any who would hold to a different view of Sinai is this: If the essence of the Mosaic Covenant is the same as the Covenant of Grace, and if the privileges of the Mosaic Covenant are the same as the Covenant of Grace, and if the context, and the requirement, and the provision, and the content, and the means of entering into the blessing in the Mosaic Covenant are all the same as the Covenant of Grace—then how can it be said that the covenant God made at Sinai with Israel was anything other than simply one of the manifestations of the Covenant of Grace?22
1 Most of the following evidences were gleaned from the writings of Puritans such as John Ball (pp102-143); Francis Roberts (pp757-764); Anthony Burgess (pp234-237); and Thomas Blake (pp202-219). Cf. also Colquhoun, Law and Gospel, pp54-62.
2 See also Luke 1:54-55, where Mary declares the same truth: “He has given help to Israel His servant, in remembrance of His mercy, as He spoke to our fathers, to Abraham and his descendants forever.”
3 “This speaks clearly and fully to the point, that by this covenant He would be their God, and they should be His people, as He had sword to Abraham, Isaac, and Jacob, that is, according to the tenor of His covenant with Abraham, etc. So that this confirms God's former covenant with Abraham, and the same covenant interest betwixt God and Abraham with his seed, and in the same way, as he had sworn to Abraham, etc; therefore these covenants were one and the same for substance.” (Roberts, p758). Of Deuteronomy 7:12, Roberts says, “Their keeping of this Sinai-Covenant, has the promise of God's keeping to them, and p