There was once a person who was traveling from place to place and he saw a palace in flames. Said he: "Can it be that there is no master to this palace?" So the owner of the palace looked out to him and said to him: "I am the master of the Palace." By the same token, because Abraham would go around saying, "Can it be that the world has no master?" G-d looked out and said: "I am the owner, the master of the world"