Sin clings to a Christian
Sin Clings to a Christian; a Non-Christian Clings to Sin.
A pious Christian is nevertheless flesh and blood as other people are. But he battles with sin and evil lust and feels what he does not like to feel (Rom. 7:15ff.); but the others are not interested and do not battle with sin and evil lust at all. To feel evil lust is of no consequence so long as one fights against it. That is why such a person must not judge according to his feeling, as though he were lost because of it. Rather he should work throughout his life against the sin which remains and which he feels. (What Luther Says #710)