I've heard this joke several times, but I'm ashamed to say I really cannot understand it. It just doesn't seem to make any sense however I look at it.
I have a suspicion that it is supposed to be rude, so I'd like to offer my apologies if it causes offence- that is not my intension.
Here's the joke:
Two nuns are in the bath.
Nun1: Where's the soap?
Nun2: Yes, it does rather.
Edit: I understand the pun on "where's"/"wears". But what I don't understand is why that is funny. Several people have mentioned that there is a sexual inference, but I don't understand where it comes from.