user
Given a cartoon image and a caption. Caption: Anything to declare? Question: Generating an explanation of why this image/caption combination is funny. Answer: 
assistant
"Anything to declare" is a question asked by customs at airports. Heaven's gates are adorned with barbed wire, implying that, oddly, heaven has as high of security as international borders. It's funny because one might assume heaven would be free of worldly security concerns, but apparently not.