A man might flatter, or bribe, or coax a tyrant; but there is no refuge from the love of God; that love will, for very love, insist upon the uttermost farthing.
Here is the quote in its fuller context.
"To regard any suffering with satisfaction, save it be sympathetically with its curative quality, comes of evil, is inhuman because undivine, is a thing God is incapable of. His nature is always to forgive, and just because he forgives, he punishes. Because God is so altogether alien to wrong, because it is to him a heart-pain and trouble that one of his little ones should do the evil thing, there is, I believe, no extreme of suffering to which, for the sake of destroying the evil thing in them, he would not subject them. A man might flatter, or bribe, or coax a tyrant; but there is no refuge from the love of God; that love will, for very love, insist upon the uttermost farthing." (George MacDonald, Justice (full sermon)).*
God is always doing his very best for each of us. (He's completely committed to our long term happiness.) Whenever he punishes, he punishes for our good.
Now it's important to know that just because a person is suffering, it doesn't mean God is punishing them (see the movie The Shack). God will cure us of our sickness. No one can resist God's perfect love forever. His will will be done.
* Those who are C.S. Lewis fans might be interested to know that George MacDonald was Lewis' favourite author. See here.