Grace is not a loophole to sin freely, but the reason it isn't is identity, not fear. You died to sin. A new heart doesn't ultimately want its old master. The answer to sin was never a fresh threat.
The Grace Answer
Paul knew this objection was coming, because clear grace always provokes it. Right after explaining that grace abounds over sin, he raises the question himself: “Shall we continue in sin that grace may abound?” His answer is emphatic: “Certainly not! How shall we who died to sin live any longer in it?” Notice what he does not say. He does not say, certainly not, because God will drop the hammer on you. He does not answer the fear question with a fear answer. He answers it with an identity answer. You died to sin. Something in your very nature changed.
This is the piece a law-based mindset always misses. It assumes the only thing keeping people from wild sin is the threat of punishment, so it panics when grace removes the threat. But that reveals a low view of what God actually does in the new birth. He does not just forgive you and then station a guard over you. He gives you a new heart with new desires. The believer who truly grasps grace does not walk away thinking, wonderful, now I can sin all I want. That reaction shows the heart never understood the love in the first place.
Freedom, not permission
Grace makes real freedom possible, and freedom includes the freedom to choose badly for a season. That is not a flaw in grace; it is what makes love genuine rather than coerced. But sin no longer has the claim on you it once did, because “sin shall not have dominion over you, for you are not under law but under grace.” Under law, sin was your master and you were losing. Under grace, sin has been dethroned. Living in it is no longer living as who you are. Not because you will be punished if you do, but because you were made for so much more than the thing you were rescued from.