Timing

My daughter forwarded this one to me:

A nun who worked with a home-care health agency was out making her rounds when she ran out of gas. As luck would have it, a gasoline station was only a block away. But when she asked the attendant to loan her a jerry-can, he told her that someone else had already borrowed it,
and had not yet returned.
Since she was on her way to see a patient, she decided not to wait. Walking back, She dug through the medical supplies in her car, and returned to the filling station with a bedpan. She filled it with gasoline, and carefully walked back to her car.

A police car halted at the nearby traffic light just as the nun began to pour the gas from the bedpan into her car.

The driver turned to his partner and said, "If that car starts, I'm turning Catholic."