Wayne Dyer, motivational speaker and writer, likes to tell an ancient story about a woman who finds a valuable stone in a river. She places the stone in a bag. Later a traveler comes to the woman and asks for something to eat. While she is reaching in the bag for a crust of bread, the traveler sees the valuable stone. He asks her to give him the stone. She readily does so and throws in some bread, as well.
The man thinks he has it made; but several days later he searches for the woman, finds her and returns the stone. He tells her that he is returning the stone in hopes of getting something even more valuable from her. The woman asks what that would be. The traveler says, "Please give me what you have that enabled you to give me that stone."