In early times in Japan, bamboo-and-paper lanterns were used with candles inside. A blind man, visiting a friend one night, was offered a lantern to carry home with him.
"I do not need a lantern," he said. "Darkness or light is all the same to me."
"I know you do not need a lantern to find your way," his friend replied, "but if you don't have one, someone else may run into you. So you must take it."
The blind man started off with the lantern and before he had walked very far someone ran squarely into him. "Look out where you are going!" he exclaimed to the stranger. "Can't you see this lantern?"
"Your candle has burned out, brother," replied the stranger.
[My interpretation of moral of the story: Never get proud of your own righteousness]