A servant goes into the marketplace in Baghdad. There he bumps into someone. When this individual turns around, the servant recognizes him as the Angel of Death.
Death glares at him, and the servant, frightened, runs away. He goes straight to his master and explains that he met the Angel of Death in the market and that he needs to get away to save himself.
The master gives him a horse, and the servant takes off, riding as fast as he can to Samarra where he knows that the Angel of Death won't find him.
Later that day, the master is in the marketplace, and he too meets the Angel of Death. The master asks him why he frightened his favorite servant. Death explains that he hadn't meant to scare him. He was just surprised.
Death said, “I was simply surprised to see him in the market. Because I have an appointment with him tonight. In Samarra.”