There are four nuns at the gates of heaven waiting to be let in by St. Peter. He goes to the first nun and says "before I let you in, I trust there's no sexual experience, for example have you ever touched a man's penis?" to which the nun replies that she once "sort of poked one". "OK" says St. Peter, "I can forgive you if you go and dip that finger in the holy water, then you can go into heaven."

The second nun comes up and St. Peter asks her "have you ever touched a man's penis?". The second nun replies "well, I once held one in my hand". St. Peter shakes his head and says "that's not good for a nun, but if you dip your whole hand into the holy water, you can go into heaven."

At that point the fourth nun barges past the third nun and says to St. Peter "can I go next, I want to wash my mouth out before she sticks her arse in it."