A man was deeply asleep one night when all of a sudden, a voice came in, “I want you to go and push that rock in front of your door.”
The man woke up. Excited, he ran to the door and saw a huge rock sitting right there. He started to push the rock. He pushed and pushed, but nothing happened. The next day, he pushed all day long again. Still, nothing. For the next three months, the man kept pushing the rock with all his might. Seeing the rock not move at all, however, he quit.
That night, the voice came in again: “why did you stop pushing the rock?”
“My Lord,” he said, “I have worked long and hard in your service, putting all my strength to do that which you have asked. Yet, after all this time, I have not even moved that rock by half a centimetre. I am failing you.”
“But, son, I did not ask you to move the rock.” The voice responded gently. “I simply asked you to push.”