When the Jews were about to enter the land of Eretz Yisrael through the Jordan River they were instructed to erect huge stones, plant them in the middle of the river, and then write the Torah on them.  Whats strange is that these stones were engulfed by the mighty river mere moments after we walked through it.  What was the point of them?  What good are monuments that sink to the bottom of a river three minutes after we erect them?  The answer might surprise you.