A man carved a wooden image of Mercury and put it up for sale in the marketplace. When no one showed interest in buying it, he tried to attract customers by loudly praising the image's virtues. He cried out, "A god for sale! A god for sale! He brings luck and keeps you lucky!"
A bystander stopped him and asked, "If this god is as wonderful as you claim, why don't you keep him and benefit from him yourself?"
The man replied, "I'll tell you why. It's true he brings gain, but he does so slowly. I need money right away."