The head nun tells the two new nuns that they have to paint their room without getting any paint on their clothes.

So the one nun says to the other, "Hey, let's take all our clothes off, fold them up, and lock the door. That way we won’t get paint on our clothes and can move more freely to get the job done faster. So they do this, and begin painting their room. Soon they hear a knock at the door. They ask, "Who is it?" "Blind man!" The nuns look at each other, then one nun says, "He's blind, he can't see. What could it hurt." They let him in. The blind man walks in and says, "Hey, nice t*ts. Where do you want me to hang the blinds?"