There was a nun who worked as a nurse at a local hospital.
She was driving the hospital van when it ran out of gas about a mile from a gas station, so she decided to walk to the gas station to get some gas, but the station didn't have a gas can for her to transport the gas back to the van.
She walked back to the van, trying to figure out what to do when she realized that she had some bed pans in the van that she could use. So, she got a bed pan and walked back to the gas station, filled it up and walked back to the van.
As she was pouring the gas into the tank, two men in a truck drove by. One said to the other, "Man, if that works, I'm turning Catholic!"