Direct Answer Based on the transcript, Luther’s redefinition of “works of the law” most directly challenges modern talk about obedience and “legalism,” because it turns Paul’s argument about Mosaic boundary markers into a blanket suspicion toward obedience to Christ. Concretely, it would require distinguishing initial salvation by grace through faith from the ongoing necessity of “godly fruit,” and refusing to label calls to obedience as automatic “works righteousness.”
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