Christians are praying that more MPs will be persuaded to reject Kim Leadbeater's assisted suicide bill when it is debated again the House of Commons on Friday.
The Westminster debate comes just days after the Scottish Parliament backed similar proposals for Scotland put forward by Lib Dem MSP, Liam McArthur.
Ciarán Kelly, director of The Christian Institute, called the bill "extremely dangerous" and said it was "no overstatement to say this is a matter of life and death".
"Should this bill become law, doctors would legally be permitted to help adults deemed to be terminally ill to kill themselves," he said.
Friday's debate will look at amendments to the bill. A final vote is expected next month.
Mr Kelly expressed dismay that hundreds of "reasonable" amendments aimed at making the legislation less dangerous have already been rejected, and that even limited safeguards have been "stripped away" in the months since MPs first voted to advance the bill to the next stage.
"It is imperative that, whenever that vote does come, MPs show up in numbers to defeat this terrible legislation," he said.
"There are many good reasons to oppose this bill: the absence of safeguards, the scope for coercion, the inevitable expansion, the impact on palliative care services, and the pressure it places on vulnerable people to end their lives for fear of being a ‘burden’.
"Most significantly, as Christians we also know the proposal breaches the Sixth Commandment and denies the value of every person as an individual made in the image of God.
"People contemplating assisted suicide are at their most desperate. Tragically, they may believe they are better off dead. Such people need a clear, firm law to protect them in these darkest moments. The law should not affirm the belief that their lives are not worth living."
The process has come under criticism for being rushed, with MPs given little time to scrutinise last week's impact report by the Department of Health and Social Care.
The report estimated that, should assisted suicide be legalised, between 164 and 787 people in England and Wales would opt for it in the first year, rising to between 1,042 and 4,559 a year by the tenth year of its implementation.
Grimly, the report also suggested that assisted suicide could save the NHS close to £60 million over 10 years.
Gordon Macdonald, CEO of the Care Not Killing coalition, which is campaigning against the proposals, said, "Under pressure to make an already stretched NHS budget cope with growing demand for its services, it is not hard to imagine a Westminster government further expanding an assisted suicide law — or the courts intervening to ensure people who are not dying are not discriminated against — as happened in Canada."
He continued, "At a time when the NHS budget is under huge strain, the UK hospice movement has a funding black hole of £150 million, and one in four patients who would benefit from quality palliative care aren’t receiving it, passing the Leadbeater and McArthur bills would be huge mistakes.
"Unless the bills are defeated, people who are elderly, disabled and dying will inevitably be placed under terrible pressures to end their lives prematurely."
