Although often identified as a Lutheran distinctive, the law-gospel distinction has been recognized by the Reformed tradition as well. Reformed theologians such as Louis Berkhof have spoken of the Bible as containing two parts–the law and the gospel. Although people often assume that this means the Bible has two testaments (the Old Testament being identified with “law” while the New Testament is identified with “gospel”), this is mistaken. In making this identification, the Reformed mean that law and gospel are two different things found throughout both testaments.
A definition or two is helpful at this point. The law is that which God demands of us (cf. Genesis 2:17; Exodus 20:1-18), while the gospel is the good news that in Jesus Christ, God freely and graciously gives to us everything which he demands of us under the law (i.e., Romans 5:9; 2 Corinthians 5:17-21). The content of the law is that which God revealed first to Adam in Eden, and then published in the covenant God made with Israel at Mount Sinai when the Ten Commandments were written down on two tablets of stone and given to the people of God (cf. Exodus 24). The gospel, on the other hand, is the content of what God has done in Jesus Christ to save us from our sins. The revelation of this gospel begins in Genesis 3:15 when God promises to rescue Adam from the curse and to crush Satan under the heal of a redeemer, and culminates in God’s promise that no longer will there be any curse (Revelation 22:3). The law is what God commands of us. The gospel is what God has done for us in Christ. The law says “do.” The gospel tells us it is “done.”
When God created Adam and placed him in Eden, Adam was created in a covenant relationship with God (the so-called covenant of works). Adam had the natural ability to obey all of God’s commands, not all of which are made known to us (although we can gather much about them). Although these commandments are written upon the hearts of all of Adam’s descendants because we are divine image bearers (Romans 2:12-16), the commandments are not published for us until God gives these commands to Israel at Mount Sinai. In this particular covenant (the Sinaitic covenant), we see how both law and gospel are found together in the Old Testament.
When God made his covenant with Israel at Mount Sinai, that which was inward (written on the human heart) was now made public for all to see and obey. The Ten Commandments are called the “moral law” because they reflect this universal knowledge of God’s will which he has implanted in every human heart. Failure to obey these commandments will bring down the covenant curses upon all those who disobey them. Fail to obey a single commandment and we are guilty of breaking all of these commandments (James 2:10). At the same time, God revealed the plans for a tabernacle (where God would be present in the midst of his people–Exodus 25:9), installed Moses as covenant mediator (Exodus 3:15), and gave the nation a priesthood complete with animal sacrifices, all of which are elements of the covenant of grace and which pointed the people of God ahead to the coming of Jesus Christ, whose death upon the cross these elements prefigured (Hebrews 8:1-13).
Although the Ten Commandments reflect the will of God with blessings promised for obedience, and curses threatened for disobedience, the law is given to Israel within a covenant context in which God provides a means for the guilt of the sins of the people to be remitted, all the while pointing them ahead to the coming of Jesus Christ. The law and the gospel, while to be carefully distinguished, are often revealed together. The commandments serve to show the people of God their sin (Galatians 3:10-14), while at the same time preparing them for the coming of Jesus Christ, their Messiah and redeemer.
As Paul puts it, “for by works of the law no human being will be justified in his sight, since through the law comes knowledge of sin” (Romans 3:20), while the gospel is the message of what Jesus Christ has done to save us from our sins (cf. 1 Corinthians 15:1-8). The law is to be obeyed, while the gospel is to be proclaimed as “good news”–that is, the gospel is the declaration of all that God has done to save sinners from the guilt and consequences of their sin (Romans 10:14-17). The law condemns and gives no power to obey its stipulations. The gospel declares that the law no longer condemns, and at the same time creates faith in the heart. We do not “do” the gospel. We “believe” the gospel.
The irony here is that because the gospel creates faith, it is the preaching of the gospel which leads God’s people into holy living (Ephesians 2:1-10: Philippians 3:2-14). The law is indeed holy, righteous, and good (Romans 7:12), but because we are sinful, when the law is preached to us, we are incited to even greater levels of sin (cf. Romans 7:5-12). But once we trust in Jesus Christ, and are united to him through faith, we will struggle with our sins, we will realize that we have failed to keep God’s commandments, and suddenly we will find ourselves desiring to obey the law (cf. Romans 7:22-23). The law does not change once we are justified. Rather, our relationship to the law changes. Before we were Christ’s, the law condemns us because we cannot keep it. The law inflicts its curse upon us. But once we trust in Christ and have died to the law and its curse, suddenly we come alive to the commandments of God, which now reveal to us the will of God, and what we may do to please him (Psalm 1:1-2).
This is why the old theologians were correct when they affirmed that the law is both the teacher of sin and the rule of gratitude. If we are not clear about the law-gospel distinction, we will not be clear about the gospel, and the fact that God has done everything in Jesus Christ to save us from our sins.