Romans 3:20 declares, “For by works of the law no human being will be justified in his sight, since through the law comes knowledge of sin.” Some interpreters have argued that Paul is speaking of two distinct laws: the ceremonial law, which could not justify, and the moral law, which continues to bind believers. This reading, however, is a later development in Christian history rather than Paul’s own intent.​

In the early church, figures like Irenaeus, Origen, Chrysostom, and Augustine typically read Paul’s reference to “the law” (nomos) as the Mosaic law in its entirety. They emphasized that the law reveals sin but does not bring righteousness, and they did not suggest that Paul was distinguishing between two different laws.

A more formal distinction emerged in medieval theology. Thomas Aquinas articulated a tripartite division of the Mosaic law: moral, ceremonial, and judicial. The moral law expressed timeless ethical principles, the ceremonial law governed Israel’s worship and sacrifices, and the judicial law regulated Israel’s civic life. Although Aquinas did not claim Paul himself made this division, his framework shaped subsequent readings of Romans.

During the Reformation, Martin Luther and John Calvin emphasized justification by faith apart from works of the law. To preserve the ongoing authority of the Ten Commandments while rejecting salvation by works, they leaned on the moral/ceremonial distinction. Calvin in particular stressed that the moral law still bound believers, while the ceremonial law had been fulfilled in Christ. This approach encouraged Protestants to interpret Romans 3:20 as if Paul were distinguishing between different kinds of law.

In the centuries that followed, Protestant confessions such as the Westminster Confession of Faith (1646) codified this division, and it became common for preachers and commentators to read Romans 3:20 through that lens. The two-law theory thus served as a theological tool in debates over antinomianism, allowing Christians to affirm both salvation by grace and the necessity of obedience.

Modern scholarship, however, has largely set aside the two-law framework as an anachronism. Studies of Second Temple Judaism have shown that Jews of Paul’s day viewed Torah as a unified covenant, not as divisible into moral and ceremonial parts. Scholars such as E.P. Sanders and proponents of the “New Perspective on Paul” argue that Paul’s concern was not with distinguishing kinds of laws but with showing that Torah as a whole cannot justify. For Paul, the law in its entirety reveals sin, but righteousness comes only through faith in Christ.

In sum, the theory that Paul spoke of two laws in Romans 3:20 reflects later theological developments, especially medieval and Reformation attempts to reconcile Paul’s teaching with the continuing role of God’s commands. While historically influential, it does not appear to be what Paul himself meant.