What if it were possible? What if the flesh wasn't weak and the spirit still willing? What if in this life it were possible to walk free of sin? If at the very least it is not your desire to be free from sin, and hope to be, have we missed the holiness of God? As much as we make excuses for why we still sin, and make it "okay", what if we thought that its not okay?
I don't mean to express legalistic notions, but sin is still sin. It is vile, despicable, and grotesque. That isn't defining us, but sin in and of itself. As others have mentioned probably, God's grace isn't a license to sin, but if you do sin God's grace is sufficient. This doesn't mean we in any way ought to entertain the lusts of the flesh. According to His word, we are not under sin's dominion.
As pleasurable as sin is for the present moment, it robs us of future joy. No, it robs us of true present joy, lasting joy. First desire, then sin, followed by death. It kills peace, it murders hope, and it slaughters happiness. Sin is an illusion, a trick, that for a second seems to offer pleasure but soon disappears into despair.
Sin ought to be denied in a believer. We are to say no to ungodliness and wordly lusts, as grace teaches us. I am not claiming to be sinless, but pray God, may I be. Righteousness that is desirable. That is pure and to be hungered after. If it is possible to walk this earth at some point to be free of sin may we all attain that goal. If its possible, let us walk in such a way. Only if. Only if. Only if.
If it is not the case, God still sanctifies us. Unto what end? Is it so much to deal with sin or to build character? Who are we? How do we conduct ourselves in practicing love? Are we givers? Do we bring peace where we go? Do we carry His presence with us? Does His light so shine upon us, others may notice a glow? Let God sanctify you, as He will unless you be, as scripture notes, a bastard. You don't even have to be concerned with not sinning at all, or else, but rather rest in Christ knowing fully well that His blood has been shed for you, and through the Spirit you have been made a child of God.
As a child of God, He will chastise and sanctify us. So who cares who claims what as it pertains to perfection? Look in the mirror, see where you stand, and if you desire righteousness cry for God to change you. Pray He sanctifies you, transforming you into the man or woman of God He has so destined you. Don't worry about perfection, let God in His process address the areas He feels you currently need fine tuning. This way you can make peace with the present, and move onward in righteousness.