Does a Christian Stop Being a Sinner?

No. And the whole comfort of the gospel depends on that answer.

Luther’s phrase is simul iustus et peccator: at the same time righteous and a sinner. It is not a fifty-fifty split, and it is not a sliding scale on which the sinner shrinks as the saint grows. In myself I remain entirely a sinner. In Christ I am counted entirely righteous. Both are fully true at the same moment, because the righteousness in question is not mine. The Apology insists on this: we are accounted righteous before God not by a quality we now possess but by Christ’s righteousness credited to us and received through faith.

Scripture says it plainly. John writes to Christians that if we claim to have no sin we deceive ourselves. Paul, an apostle, speaks in the present tense about doing what he hates and cries out for deliverance. He tells the Galatians that the flesh and the Spirit are at war within them so that they do not do what they want. None of that is written about the unconverted.

This does not make sanctification optional or unreal. Luther put the shape of it in the catechism: baptism means the old Adam in us is drowned by daily contrition and repentance, and the new man daily emerges to live before God in righteousness. Note the word daily. The old Adam has to be drowned every day because he can swim. Real good works follow real faith as certainly as fruit follows a good tree — but they are never the ground of our standing and never the thing a troubled conscience is permitted to rest on.

Rahab is the clearest case in Scripture. Fifteen centuries after Jericho, in the two New Testament passages that hold her up as an example — one for her faith, one for her works — the apostles still call her Rahab the prostitute. James commends her obedience and keeps the label in the same sentence.

So the honest answer to “am I still a sinner?” is yes, today, right now. And you are righteous, today, right now, because that righteousness was never yours to begin with.