2 Samuel 13 tells how Amnon, son of King David, became consumed with desire for his half-sister Tamar. Of course, his desire was a moral dead end; it could never be lawfully fulfilled. But Amnon dwelt on it until his frustration began to have a visible effect on him.
Amnon’s distress caught the attention of his friend Jonadab. The two young men were cousins, in fact: Jonadab was the son of Shimeah, a brother of King David. The Bible describes Jonadab as “shrewd” (Hebrew chakam). The word can mean skillful, wise, or prudent;…