I heard a wonderful drasha on the verse II Samuel 1:18 but I can't find the source:
ויאמר ללמד בני־יהודה קשת הנה כתובה על־ספר הישר
He instructed to teach the Children of Yehudah the bow. Behold it is written in the Book of Yashar.
King David was describing the great spiritual power of King Saul. He had such a great strength of will that he could directly fight his own inclination to do evil, ie. face-to-face with the sword, but now that he was dead nobody else was able to prevail in this manner. Now people had to be taught to fight temptation from afar, ie. with a bow and arrow. They had to avoid temptation by using all manner of strategies and forward planning so that they were not faced even with the opportunity to do wrong.
I know of other sources for this same idea, but I cannot find the source of the drasha from this specific verse.