If anyone is in Christ, he is a new creation. Not a repaired one, not a better managed one. New.
We tend to experience it as improvement, which is why the verse can feel overstated. You still recognize yourself. The same habits show up, the same temperament, often the same failures on a slightly longer cycle.
But Paul is not describing your felt experience. He is describing a status that has already changed, whether or not the evidence has caught up. Those two things run on different timetables, and mistaking one for the other causes an enormous amount of unnecessary despair.
The old has passed away. Past tense, already done. Behold, the new has come.
Which means the work ahead of you is not becoming someone new. It is gradually catching up with someone you already are.
That is a different kind of effort. Less anxious, considerably more durable.
