C.S. Lewis likened God's use of adversity to walking a dog. If the dog gets its leash wrapped around a pole and tries to continue running forward, he will only tighten the leash more. Both the dog and the owner are after the same end, forward motion, but the owner must resist the dog by pulling him opposite the direction he wants to go. The master, sharing the same intention but understanding better than the dog where he really wants to go, takes an action precisely opposite to that of the dog's will. It is in this way that God uses adversity.
-C.S. Lewis, Mere Christianity