With six days to go before Friday’s historic Commons showdown on assisted dying, it’s the opponents who are turning up the heat.

The explosive attack on the bill by Shabana Mahmood follows the poignant and personal plea from Gordon Brown to MPs to reject the bill.

We knew the justice secretary is opposed to the bill. She has already made that clear. But her attack on it, in a letter to constituents, is brutal.

Read more: UK on ‘slippery slope’ to ‘death on demand’, warns justice secretary

She talks about a “slippery slope towards death on demand”. Savage. The state should “never offer death as a service”, she says. Chilling.

So much for Sir Keir Starmer attempting to cool the temperature in the row by urging cabinet ministers, whatever their view, to stop inflaming or attempting to influence the debate.

Ms Mahmood talks, as other opponents have, about pressure on the elderly, sick or disabled who feel they have “become too much of a burden to their family”.

She hits out at a “lack of legal safeguards” in the bill and pressure on someone into ending their life “by those acting with malign intent”.

Malign intent? Hey! That’s quite an assertion from a secretary of state for justice and lord chancellor who’s been urged by the PM to tone down her language.

It’s claimed that Sir Keir ticked off Wes Streeting, the health secretary, after he publicly opposed the bill and launched an analysis of the costs of implementing it.

Read more: Where does the cabinet stand on assisted dying?

Will the justice secretary now receive a reprimand from the boss? It’s a bit late for that. Critics will also claim Sir Keir’s dithering over the bill is to blame for cabinet ministers freelancing.

Shabana Mahmood is the first elected Muslim woman to hold a cabinet post. Elected to the Commons in 2010, she was also one of the first Muslim women MPs.

She told her constituents in her letter that it’s not only for religious reasons that she’s “profoundly concerned” about the legislation, but also because of what it would mean for the role of the state.

But of course, she’s not the only senior politician with religious convictions to speak out strongly against Kim Leadbeater’s bill this weekend.

Gordon Brown, son of the manse, who was strongly influenced by his father, a Church of Scotland minister, wrote about his opposition in a highly emotional article in The Guardian.

He spoke about the pain of losing his 10-day-old baby daughter Jennifer, born seven weeks prematurely and weighing just 2lb 4oz, in January 2002, after she suffered a brain haemorrhage on day four of her short life.

Read more: Gordon Brown says assisted dying should not be legalised

Mr Brown said that tragedy convinced him of the value and imperative of good end-of-life care, not the case for assisted dying. His powerful voice will strongly influence many Labour MPs.

And what of Kim Leadbeater? It’s looking increasingly as though she’s now being hung out to dry by the government, after initially being urged by the government to choose assisted dying after topping the private members bill ballot.

All of which will encourage Sir Keir’s critics to claim he looks weak. It is, or course, a private members bill and a free vote, which makes the outcome on Friday unpredictable.

But the dramatic interventions of the current lord chancellor and the former Labour prime minister are hugely significant, potentially decisive – and potentially embarrassing for a prime minister who appears to be losing control of the assisted dying debate.