From 31 January any mention of the word Brexit will officially be punishable by death. Anyone who is even suspected of thinking about Brexit will be condemned to a public show trial. As far as the government is concerned, the UK will have left the EU and that’s an end to it. Even to discuss the details of a future arrangement will be considered grossly unpatriotic, with offenders being sent to re-education camps.

This is the way the Brexit department ends. Not with a bang, but by being airbrushed out of history. And to mark the occasion of his department’s final question session in the Commons, Stephen Barclay was determined to end his ministerial career as he had started it – with complete and utter anonymity. For Barclay it is a matter of pride to never say anything memorable. His whole job as Brexit secretary was to do next to nothing and he has fulfilled the brief superbly. At times he has even uttered sentences that have put himself to sleep.

“Is this the end of the department?” said Hilary Benn plaintively. The chairman of the Brexit select committee can see his own position disappearing at the very moment when he knows his job was really only just beginning. Another reason why Dominic Cummings was so keen to see the end of the Brexit department. Parliamentary scrutiny is for losers.

It looks that way, Barclay shrugged. He did not seem unduly bothered that his department was being wound up prematurely. Why should he? He knows there will always be a place in government for someone who can effortlessly fill dead air with even deader air and Boris Johnson is sure to offer him something else. Not least when there are other deadbeats such as Andrea Leadsom and Liz Truss whom he can easily replace. That’s one of the joys of the current cabinet. So many jobs, so little talent.

Barclay’s voice melted into liquid Mogadon as he tried to fill the unforgiving, inconsequential hour. His first task was to reassure everyone on the Tory benches that “The Word That Couldn’t Be Mentioned After 31 January” would be properly celebrated across the nation. Special ales would be brewed, flags would be waved, Big Ben would carry on ringing until the bell became detached from its moorings and the tower was turned to rubble.

And from now on, between 11 and 11.30 in the morning, every citizen would be expected to participate in a daily collective act of gratitude for the country’s deliverance from the EU by prostrating themselves before statues of a naked baby Boris being swaddled by Classic Dom: The Madomma and Child.

Pulling down his trousers to reveal some Union Jack toilet paper hanging out of his underpants, Tory John Hayes was the first of many to assert that 30 minutes wasn’t nearly long enough.

Tim Farron briefly chipped in to say that it might be an idea to remember that more people had voted for parties supporting remain than The Word That Couldn’t Be Mentioned After 31 January at the recent election, so if the government was serious about uniting the country, a good place to start would be to dial down the triumphalism. Barclay looked astonished, as if it had genuinely never occurred to him that some people might not be entirely jubilant at the UK’s departure from the EU, but reluctantly agreed to set up a helpline for traumatised remoaners. An 0800 number, charged at 45p a minute, where callers would be kept on hold for 75 minutes before being told to bugger off by someone in an overseas call centre.

Apart from junior minister James Duddridge making a point of rubbishing Dominic Grieve – a particularly graceless piece of grandstanding from a man who has never yet found a principle he wouldn’t trade to progress his career – the rest of the session passed with MPs doing little more than going through the motions. The third Brexit minister, Robin Walker, couldn’t even be bothered to speak. There again, there wasn’t anything to say. The government can now do exactly as it wants and all the sting has gone out of the Brexit debate.

Even Keir Starmer sounded only passingly interested as he reminded Barclay that while the government may have won the vote on child migrants – Johnson has enough trouble keeping track of his own children without having to bother about a whole load of Syrian kiddies – Labour had won the moral argument. Then Starmer also has the small matter of a leadership election to concentrate on. Not easy when the congenitally hopeless Barry Gardiner had just thrown a curveball by suggesting he might also stand. Was this Bazza’s idea of a joke? It’s hard to think of someone who would make a worse Labour leader. Other than Richard Burgon. No wonder Starmer always looks permanently startled.

It was a morning of endings. At business questions, there was a rare sighting of Jacob Rees-Mogg, who has been kept hidden since the opening day of the election campaign when he screwed up so catastrophically by revealing his true personality. With an 80-seat majority the ERG are now irrelevant and Jacob’s days in cabinet are numbered. Just how toxic he now is was soon apparent. Not one of his colleagues joined him on the frontbench for what is sure to be one of his final appearances as Commons leader.

Rees-Mogg tried to make light of his isolation, but the pathos was unavoidable. Hubris has caught up with him. He tried to sound sincere about the Australian bushfires. But everyone knew that what he was really thinking was that the humans, koalas and kangaroos who had been burned to death were just a bit dim. If only he had been there; he would have known exactly how to escape the fires.