At Friday night services, Morris went to his friend Irving and said, "I need a favor. I'm sleeping with the Rabbi's wife. Can you hold him in synagogue for an hour after services for me?" Irving was not very fond of the idea, but being Morris' lifelong friend, he reluctantly agreed.
After services, he struck up a conversation with the Rabbi, asking him all sorts of stupid questions - just to keep him occupied.
After some time the wise Rabbi became suspicious and asked, "Irving what are you really up to?"
Irving, filled with feelings of guilt and remorse confessed to the Rabbi, "I'm sorry, Rabbi. My friend is sleeping with your wife right now, so he asked me to keep you occupied."
The Rabbi smiled, put a brotherly hand on Irving's shoulder and said, "You'd better hurry home, Irving. My wife died two years ago."