LONDON — Many hours into a parliamentary session that was not supposed to happen, one female lawmaker after another pleaded with Prime Minister Boris Johnson on Wednesday to soften his rhetoric, to stop accusing people of betrayal for disagreeing with him over Brexit, if for no other reason than their own safety.
But Mr. Johnson dug in. Looking none too pleased to have been dragged back to Parliament for an unexpected sitting after the Supreme Court ruled that his efforts to sideline lawmakers were unlawful, he suggested that recalcitrant lawmakers had only themselves to blame for the climate of hostility and even violence that has enveloped British politics.
“I’ve never heard such humbug in all my life,” Mr. Johnson said after a Labour lawmaker, Paula Sherriff, spoke of getting death threats that quoted Mr. Johnson’s words.
Then Tracy Brabin, another Labour lawmaker, stood up to speak. She had been elected to her seat after the killing of Jo Cox, a Labour member of Parliament who was murdered in the run-up to the 2016 Brexit referendum by a man shouting “Britain first.” Ms. Brabin, too, asked Mr. Johnson to tone down his language.
Instead, Mr. Johnson repeated it, accusing lawmakers of an act of “surrender” and “capitulation” for trying to stop him from pulling Britain out of the European Union without a deal governing future relations.
“The best way to honor the memory of Jo Cox and indeed the best way to bring this country together would be, I think, to get Brexit done,” Mr. Johnson said, a statement that was met with no small measure of disbelief.
For a prime minister known for provocative and sometimes intemperate comments and behavior, and who built his career on newspaper columns that observers said sometimes veered into racism and sexism, the eruption was not entirely out of character.
But having dressed up the sort of language he once used in a right-leaning newspaper column in all the ceremony of Parliament, Mr. Johnson still startled onlookers.
“I don’t know why I’m ever shocked at how low Boris Johnson can go,” Jess Phillips, a Labour member of Parliament, said in a television interview in addressing the prime minister’s remarks about Ms. Cox. “For him then to use the memory of my dead friend, who was murdered in the street, to try and hammer home one more time his point — the only person who has surrendered anything is Boris Johnson and he’s surrendered his morality.”
Parliament was sitting only after the Supreme Court decided on Tuesday that Mr. Johnson’s plan to suspend the body for five weeks had been unlawful. The prime minister was concerned that lawmakers would meddle in his plans to complete Brexit by Oct. 31, but the judges said he had gone too far.