Nuns discussing drinks

Arthur was sitting outside his local pub one day, enjoying a quiet pint and generally feeling good about himself, when a nun suddenly appears at his table and starts decrying the evils of drink. “You should be ashamed of yourself young man! Drinking is a Sin! Alcohol is the blood of the devil!” Now Arthur gets pretty annoyed about this, and goes on the offensive. “How do *you* know, Sister?” “My Mother Superior told me so” “But have you ever had a drink yourself? How can you be sure that what you are saying is right?” “Don’t be ridiculous – of course I have never taken alcohol myself” “Then let me buy you a drink – if you still believe afterwards that it is evil I will give up drink for life” “How could I, a Nun, sit outside this public house drinking?!” “I’ll get the barman to put it in a teacup for you, them no-one will know” The Nun reluctantly agrees, so Arthur goes inside to the bar. “Another pint for me, and a triple vodka on the rocks”, then he lowers his voice and says to the barman “… and could you put the vodka in a teacup?” “Oh no! It’s not that drunken Nun again is it?“