Two Words, Rightly Divided

Luther described scripture as containing two fundamentally different kinds of speech, which he called law and gospel, and argued that a preacher's whole competence rests on telling them apart. Law is every word of scripture that commands, demands or accuses: it tells a person what to do and, more painfully, shows how far short of it they fall. Gospel is every word that simply gives, announcing what God has already done in Christ, without conditions attached. The distinction is not a division of the Bible into an Old Testament of law and a New Testament of gospel; both words run through both testaments, and the Sermon on the Mount can preach law as sharply as the Ten Commandments preach it, while a psalm of confidence in God's mercy can preach gospel as purely as any verse of Paul.

The stakes, in Luther's account, were pastoral before they were theoretical. Preach law without gospel and a congregation is left crushed under demand with no word of rescue. Preach gospel without law and sin is never truly named, so grace is received as a permission rather than a rescue, because the danger it answers was never made real. Rightly dividing the two meant applying law to whoever felt secure in their own righteousness and gospel to whoever had been brought to despair by the law's accusation, a pairing that had to be renewed sermon by sermon rather than settled once for a congregation as a whole.