It is hard not to point a finger at Martin Luther for creating a counterforce between law and gospel. In fact, contrasting the two — one to condemn and one to bring grace — is at the heart of the Lutheran dialect, or how the Lutheran is taught to read the Bible. Nothing can be achieved by obedience to the law; all that can be achieved is achieved in Christ. The Reformed, those who follow from Calvin, involved themselves in a more nuanced way in the issue of how the law and the gospel are related. A good example of this approach is found in a statement by John Stott: “the law sends us to Christ to be justified, and Christ sends us back to the law to be sanctified.” There is considerable debate over this issue among evangelicals today.
This problem is created by tidy systematic formulas, and I appreciate the nuances and discussions and light that systematicians sometime shed, but in this case something has gone terribly wrong. The immediate problem is that the debate often assumes that law demands performance while the gospel expects only faith. Beside the importance of what the New Perspective on Paul brings to the discussion, not the least of which is a radical reshaping of how Judaism worked as a religion and that “works of the law” are not just Torah but the special laws that separated the Jew from the Gentile, the contrast Paul makes between works of the law and faith does not result in the latter not having law or performance. After all, in one of his quintessential statements in Ephesians 2:8-10, Paul overtly argues Christians are created by God “to do good works” (which is performance by any other name).
As one sympathetic to the Anabaptists I believe in salvation by faith and not by works, and to their credit the Anabaptists have always taught the demand of discipleship in a way more emphatically central than most. Radical distinctions, often made by major theologians in the Protestant traditions, between justification and sanctification are unwise because they are not grounded in the Bible. The Torah is God’s revelation to God’s people and to be read as God’s gracious demand. God graciously reveals what God wants, but God unfolds that demand over time so that it is completely revealed only in Christ; God graciously provides the power for us to do what Jesus teaches as we live in the Spirit in the light of the coming kingdom; and God graciously demands how God wants us to to live in the Sermon and in the ethical exhortations of the New Testament.
In other words, in Jesus’ demand to live righteously, which runs through the Sermon, we see an Ethic from Above, from Below, and from Beyond* — but it is an ethic his followers are to perform. The best way to preach the Sermon is to preach what it is: a demand on the disciple.
Scot McKnight, Sermon on the Mount (The Story of God Bible Commentary)
*Earlier in the book these terms are explained: “Ethic from Above: Torah,” “Ethic from Beyond: Prophets,” and “Ethic from Below: Wisdom.”