The Pope has it but he does not use it. Your father has it but your mother uses it. Nuns do not need it. Your lady friend's husband has it and she uses it. What is it?
I weaken all men for hours each day.
I show you strange visions while you are away.
I take you by night, by day take you back,
None suffer to have me, but do from my lack.
What am I?