The Simpsons Season 17 Episode 14

Marge: Where's Bart? I haven't seen him since you came home.
Homer: (sarcastic) Oh, you haven't seen Bart for a few hours, so you automatically assume I let something terrible happen.
Marge: I didn't say that!
Homer: I know what you think. When stupid Homer wasn't looking, Bart got kidnapped by a monkey.
Marge: I could never think something that horrible!
Homer: And now I'm using sarcasm to confess the whole thing, so later I can say that I already told you!
Marge: Sorry I asked. (leaves table)
Lisa: Dad, you can't keep this up for long.
Homer: Oh, you're so right! I guess I should be more concerned with Bart's safety than covering my own butt! And maybe I'm talking like this because I can't stop! Help me, Lisa, I have serious mental problems!