Two nuns were driving alone out in the boonies.
They ran out of gas.
Fortunately they could walk to a gas station not far away, where they asked to purchase a can of gasoline.
"I'm sorry, sister," said the attendant, "but all I have for you to carry it in is an old chamber pot.
The nuns agreed that this would be fine.
They returned to the car.
As they were pouring the gasoline into the tank, a man drove by, stopped his car, and said, "Oh sister, if only I had your faith."