Maybe there is humor that we don't even know about because of our culture. Humor is a cultural thing and what's funny in one culture might just be a simple or stupid statement in an other.
2 Kings 2: 23 Then he went up from there to Bethel; and as he was going up by the way, young lads came out from the city and mocked him and said to him, "Go up, you baldhead; go up, you baldhead!" 24 When he looked behind him and saw them, he cursed them in the name of the LORD. Then two female bears came out of the woods and tore up forty-two lads of their number.
This from John 13:10 (NIV)
Jesus answered, "A person who has had a bath needs only to wash his feet; his whole body is clean. And you are clean, though not every one of you."
I always thought Jesus was implying that the disciples were smelly and therefor funny. However verse 11 continues...
For he knew who was going to betray him, and that was why he said not every one was clean.