What he understands perfectly well is that the standard fallback position for blowhard bullies who’ve just said something so blitheringly stupid that anyone with the brains God gave a Cheerio could refute them is, “Oh, I was just KIDDING! I was just being sarCASTic! Don’t you got no sense of HUMOR?”
See, it’s just that you’re just too stupid to see how clever he is. All your fault.
Keep it up and he’ll sic his brownshirts on you. He’s promised to pay their legal fees.