It happened once that the Mullah Nasruddin was sitting in the town square, enjoying the midday sun and  eating something, when a passer-by stopped and looked at him aghast.

“Mullah!” said the man, “what are you doing? Don’t you know that it is the time of the fast? You’re not supposed to eat anything! And certainly not in public!”

“Oh, yes,” said the Mullah, “I know.  I only do it out of modesty.”

“Modesty?” said the man in confusion. “What has modesty got to do with it?”

“It’s the sin of pride to make a show of our virtues,” Nasruddin said.  “I eat in public so that people will not know I’m fasting.”