Why this absenteeism? Where were Boris Johnson’s troops? It was impossible not to see, in the gaps on the green benches, a protest against his leadership. A considerable number of his followers had not turned out to defend him.

Johnson set out to defend himself. He did so by attacking Sir Keir Starmer for having taken money from the law firm Mishcon de Reya.

In other words, the Leader of the Opposition is a hypocrite, who in “a classic lawyerly way” (Johnson’s words – he knows how unpopular lawyers are) prosecutes other people for the kind of thing he has done himself.

Sir Keir did not sound very lawyerly as he said the PM was “a coward, not a leader”. The tone was more that of a man in a pub who is desperate to provoke a fight.

“When somebody in my party misbehaves I kick them out,” Sir Keir added. “I lead, he covers up.”

Johnson tried to subvert PMQs by asking Sir Keir some insulting questions. The Speaker, Sir Lindsay Hoyle, got very angry, and silenced the Prime Minister: “In this House, I’m in charge.”

The PM proceeded to accuse Sir Keir of “Mishconduct”, a reference to Mishcon de Reya: the word “misconduct” would be unparliamentary.

Did this inglorious dodge work? Perhaps by distracting attention it did. The vehemence with which Johnson spoke demonstrated fighting spirit, which is one of the qualities required by any PM when the Chamber becomes a bear pit.

And it is possible that he will provoke his opponents into such extravagantly pious utterances that they will indeed end up sounding like hypocrites.

But Ian Blackford, for the SNP, pointed to the gaps on the Tory benches, and remarked that “the rebellion has clearly started”. He sought to rile Johnson by remarking that the last nine Tory Treasurers have been elevated to the House of Lords.

The Prime Minister switched tack, and became pious himself. These “constant attacks on the UK’s levels of corruption and sleaze” were doing the country a massive disservice: “This is one of the cleanest democracies in the world and people should be proud of it.”

His voice was hoarse, and he almost choked as he made this declaration of innocence.

Jake Berry (Con, Rossendale and Darwin), a long marcher who was with Johnson in the early days of his eventually successful leadership bid, asked whether the voters of the North were right to take the PM “at his word” as far as promises about Northern Powerhouse Rail are concerned.

Johnson, who cannot have been pleased to have his good faith doubted by his old comrade in arms, replied: “Yes. He should wait and see what is unveiled tomorrow when he may learn something to his advantage.”

Michael Fabricant rose immediately after PMQs on a point of order and pointed out that the Leader of the Opposition had called the PM “a coward”, which was surely a breach of the rules.

The Speaker said the Leader of the Opposition must withdraw the word. Sir Keir, who looked as if he had been expecting this, rose and said: “I withdraw it [theatrical pause], but he’s no leader.”

“Coward” is not quite the right word to throw at Johnson, who today demonstrated that he is not afraid of having a fight. The more worrying question for him is how many of his own MPs are willing to join him in that fight.