A priest and a rabbi operated a church and a synagogue across the street from each other. Since their schedules intertwined, they decided to go in together to buy a car.
After the purchase, they drove it home and parked in on the street between their establishments. A few minutes later, the rabbi looked out and saw the priest sprinkling water on their new car. It didn't need a wash, so he ran out and asked the priest what he was doing.
"I'm blessing it," the priest replied. The rabbi considered this a moment, then said, "Oh," and ran back inside the synagogue. He reappeared a moment later with a hacksaw, ran to the back of the car and cut off the last two inches of the tailpipe.