One day, while David was fighting the Philistines, he complained that he was thirsty. There was a well over near where the Philistines were encamped. So three of David’s best warriors risked their lives to bring him some water from that well. But then David refused to drink it, claiming that they had brought him blood instead of water. He poured the water out on the ground.

The end.

The moral of the story

Don’t bother doing favors for David.