Luther's bad exegesis of Romans 6–8

Luther attempted in several ways to express the permanent, and structurally basic, incongruity of grace in the life of a believer, most famously in the phrase simul justus et peccator. The strongest exegetical base for that notion comes from Romans 6-8, but it draws on what now seems to most a faulty reading of Romans 7-8 as a dialectical depiction of two dimensions of the Christian life. If, to the contrary, 7:7-25 describes life “in the flesh” before becoming a believer (cf. 7:5), not a continuing aspect of the believer’s life, Luther’s simul . . . peccator looks less convincing.—J. M. G. Barclay, Paul and the Gift, 501–2

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Personally, I never bought into Luther's bad exegesis. A book was recently published that takes a look at the exegesis of Romans 7 over the years: Conquerors Not Captives: Reframing Romans 7 for the Christian Life, by Joseph R. Dodson. Take a look at it.
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