W. Austin Gardner
Sin is costly

When you profit from the devil, he will send you a bill! When you accept favors from the world, they will one day let you know what your obligations are—and those obligations will put you in very difficult situations. Evil extracts a high price. You will have to compromise and deny your faith in order to satisfy the obligations evil puts on you. You will have to fight against that which you formerly supported. The world is a hard taskmaster. It can smile real nicely when you need help, but when it comes to collect it has a stern face; and you dare not refuse paying your due without risking serious trouble. So David was in a real mess.
John G. Butler, David: The King of Israel, vol. Number Fifteen, Bible Biography Series (Clinton, IA: LBC Publications, 1998), 385.
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