Pickles it is easy.. put yourself in Paul's shoes. You are Paul. You heal ALL people you ask God to heal. Even roughnecks on an island, after an ADDER bit you and you did not even flinch, because not even snake poisen can touch you. You can make the sea even into a storm. You can tell people if they leave the ship they will die... You are an amazing person God uses as a vessel to carry the Gospel to the world. And then you get to a city where a decent man is sick. This man you know by name and he is a fellow believer as yourself, so much so that you will write about him to your dearest student Timothy...
And yet after also wishing you friend heaalth, he remained sick.... Of coarse you will have to ask your Lord what this meant! And the answer God will give you, Paul, should serve as LESSONS for others, even Cobus has to know. That is why God included this in His Word!
Is it just not GRACE?