It is worth remembering where this was written. Not from a comfortable study but from custody, by a man with a genuinely uncertain future.
That changes how the passage lands. This is not advice from someone whose circumstances were cooperating. It is a report from someone who found something that held when they did not.
Notice also the mechanics. Paul does not say stop feeling anxious. He gives a redirect: in everything, by prayer, with thanksgiving, tell God. Anxiety is not being suppressed, it is being relocated.
And the promise is not that you will understand. It says the peace surpasses understanding, meaning you may well have peace and confusion simultaneously, and be unable to explain to anyone why you are not falling apart.
That is not denial. That is being guarded.
