Slave to Something
With his brief introductory question, What then? the apostle again anticipates the false conclusions his antagonists would derive from his declaration that believers “are not under law, but under grace” (v. 14b). To them, the idea of no longer being under law but under grace was tantamount to being free of all moral restraint.
The doctrine of grace has always been subject to that false charge, which the apostle first answers in the first half of chapter 6. But because the misunderstanding was so common and the issue so critical, he gives the answer again from a slightly different perspective. The doctrine of salvation by God’s grace, working only through man’s faith and apart from any works, is the furthest thing from a license to sin.