LONDON — A day after suffering a crushing rebuke from his country’s highest court, a notably unchastened Prime Minister Boris Johnson appeared before a hastily reconvened Parliament and doubled down on his hard-line Brexit approach.

If anyone had expected Mr. Johnson to appear before the lawmakers hat in hand after being forced to cut short a trip to the United Nations and return back home, they were presumably disappointed.

“Come on!” Mr. Johnson yelled over a barrage of jeers as he urged his opponents to stage a vote of no confidence in him.

“Humbug,” he declared, when one Labour lawmaker, Paula Sherriff, made an emotional plea for him to stop using inflammatory language.