A little boy was spending his Saturday morning playing in his sandbox.  He had with him his box of cars and trucks, his plastic pail, and a shiny, red plastic shovel.  In the process of creating roads and tunnels in the soft sand, he discovered a large rock in the middle of the sandbox.

The boy dug around the rock, managing to dislodge it from the dirt.  With no little bit of struggle, he pushed and nudged the rock across the sandbox by using his feet.  (He was a very small boy and the rock was very large.)  When the boy got the rock to the edge of the sandbox, however, he found that he couldn't roll it up and over the little wall.

Determined, the little boy shoved, pushed, and pried, but every time he thought he had made some progress, the rock tipped and then fell back into the sandbox.  He grunted, struggled, pushed, and shoved; but his only reward was to have the rock roll back, smashing his chubby fingers.  Finally he burst into tears of frustration.

All this time the boy's father watched from his living room window as the drama unfolded.  At the moment the tears fell, a large shadow fell across the boy and the sandbox.  It was the boy's father.  Gently but firmly he said, "

"Son, why didn't you use all the strength that you had available?

Defeated, the boy sobbed back, "But I did, Daddy, I did!  I used all the strength that I had!"

"No, son," corrected the father kindly. "You didn't use all the strength you had.  You didn't ask me."