Justice WIth The Farmer

What's the story behind the title? 

"So you have sold the well to the farmer but not the water?" Birbal asked the neighbor. 

"Do you agree that owner of well is the farmer & you are owner of water?" Birbal asks further.

"Exactly!", neighbor replied.

Birbal now points towards the valid question - "So you need to pay rent for keeping your water in his well, or take out all of the water out of well. Don't you?"

By now the neighbor realized that he was outwitted. He had no option other than to apologize & take back his claim.