A lecture about English
A linguistics professor was lecturing to his English class one day. "In English," he said, "A double negative forms a positive. In some languages, though, such as Russian, a double negative is still a negative. However, there is no language wherein a double positive can form a negative."

A voice from the back of the room piped up, "Yeah, right."

A Lutheran pastor, a Catholic priest and a Rabbi...
A Lutheran pastor, a Catholic priest and a Rabbi were fishing from a boat not from the lake shore. The pastor had to make a trip to the port-a-potty located on the shore, so he got out of the boat, walked across the water and in the same matter, came back to the boat after he was finished. A little later, the priest had to make the trip also. He got out of the boat, walked across the water, visited the bathroom and in the same manner, came back to the boat. Still later, the rabbi needed to go ashore. He got out of the boat and immediately sank. The pastor looked at the priest and said,"Do you think we ought to tell him where the rocks are?"