Greed is a hunger that can never be filled. The more the fisherman's wife receives, the more she wants. No amount of power or luxury satisfies her, because she is not grateful for what she has — she only thinks about what she does not have yet.
This story was collected by the Brothers Grimm and published in 1812. It is one of their most powerful moral tales. The sea itself becomes a character — calm and blue when the wishes are small, dark and stormy when the demands become outrageous. The changing sea reflects the moral state of the story.
The fisherman in this tale is a sympathetic but weak character. He knows his wife's demands are wrong, but he goes back to the fish every time because he cannot say no to her. His weakness enables her greed. The story warns us not only about wanting too much, but also about the danger of not standing up for what we know is right.