To me, this is a song about mistakes you make in life, and forgiveness. "Tell me a dirty joke, and I'll laugh it off lightly, if I tell you a dirty joke you might not like me." is saying that you shouldn't let petty things come between you and just to forgive and move on. Also, I think it is saying that even if someone makes a huge mistake, if you love them, you should forgive them becuase its not worth it to lose someone over one mistake.
To me, this is a song about mistakes you make in life, and forgiveness. "Tell me a dirty joke, and I'll laugh it off lightly, if I tell you a dirty joke you might not like me." is saying that you shouldn't let petty things come between you and just to forgive and move on. Also, I think it is saying that even if someone makes a huge mistake, if you love them, you should forgive them becuase its not worth it to lose someone over one mistake.