Three Uses of the Law

Definition and Meaning

The three uses of the law (Latin triplex usus legis) is a teaching of Protestant theology that distinguishes three functions of the Old Testament law, especially the moral commandments summarized in the Ten Commandments. These uses are often described metaphorically as a curb, a mirror, and a guide.

• Civil use (curb): Through fear of punishment, the law restrains human wickedness and preserves social order.
• Theological use (mirror): The law shows people their own sin and inability, prompting them to seek grace and come to Christ.
• Didactic use (guide): For believers who have already been justified by faith, the law teaches the will of God and serves as a guide for holy living. This is also called the "third use."

The order varies by tradition. Lutheran theology generally lists the civil use first and the use that convicts of sin second. John Calvin, in his Institutes of the Christian Religion, treated the use that convicts of sin first.

Biblical and Historical Background

The following passages are commonly cited in support of this distinction. For the use that convicts of sin, Romans 3:20 and Galatians 3:24 are cited. The New Korean Revised Version renders the law in Galatians 3:24 as an "elementary teacher" that leads to Christ (the KJV reads "schoolmaster"). For the use that restrains evil, 1 Timothy 1:9–10 is cited, and for the use that guides believers, Romans 3:31 and Psalm 119:97–104 are cited.

Martin Luther emphasized chiefly the first two uses and stressed the distinction between law and gospel. Luther's colleague Philip Melanchthon is credited with systematically formulating the three uses. Within Lutheranism the third use became a matter of controversy, which the Formula of Concord (1577) resolved in favor of affirming it. Calvin called the third use the "principal use" of the law, and later Reformed confessions followed this framework. Chapter 19 of the Westminster Confession of Faith states that although believers are not justified by the law, the law is of benefit to them as a rule of life.

Practice in the Korean Church

Churches in the Reformed tradition, including Korean Presbyterian churches, generally teach all three uses. They place particular emphasis on the third use in connection with sanctification, which follows justification. The Heidelberg Catechism treats the law in two places: in its early section as a mirror that reveals human misery, and in its later section as the Ten Commandments that guide a life of gratitude. This structure is frequently highlighted in catechetical instruction.

The Lutheran Church in Korea, following the Lutheran tradition, teaches this subject with the distinction between law and gospel at its center. Methodist and Holiness churches, under the influence of Wesleyan theology, tend to hold that the law continues to serve in the sanctification of believers.

In pastoral practice, the Ten Commandments are used in evangelism to bring people to an awareness of sin, and in Christian education they are taught as a guide for the believer's life. At the same time, many denominations share the concern that overemphasizing the law leads to legalism, while making light of it leads to license.