A man in Amsterdam feels the need to confess, so he goes to his priest.
"Forgive me, Father, for I have sinned. During world war II, I hid a refugee in my attic."
"Well," answers the priest, "that's not a sin."'
"But I made him agree to pay me 20 guilders for every week he stayed."
"I admit that wasn't good, but you did it for a good cause."
"Oh, thank you, Father. That eases my mind. I have one more question."
"What is that, my son?"