Paul just told us that believers are no longer slaves to sin. So, does that mean we can just do whatever we want? This verse tackles that potential misunderstanding head-on.
Paul anticipates a dangerous question: If we're not under the strict rules of the Law, but under God's amazing grace, does that give us permission to sin? His answer is a resounding 'No!'
The Misunderstanding
Some might hear 'under grace' and think it means freedom from any accountability. They might reason, 'The Law condemns, but Grace forgives, so why worry about sinning?' This thinking twists God's gracious gift into a license for rebellion.
The Reality
Being 'under grace' means we are under God's unmerited favor and empowering presence. It's not a get-out-of-jail-free card for sin. Instead, grace empowers us to live righteously, not to indulge in sin. Paul's immediate 'By no means!' (or 'God forbid!') shows how abhorrent this idea is.