How can he explain it

An old gentleman was walking slowly along a street one day when he saw a little boy who was trying to reach a door which was too thigh for him. He was a kind-hearted old man, so he stopped and said, "I will ring the bell for you," and then he pulled the bell so hard that it could be heard all over the house.
The little boy looked up at him and said, "Now we will run away. Come on," and before the old gentleman knew what has happening, the naughty boy had run round the corner of the street, leaving the man to explain to the agry owner of the house why he had rung the bell.