THE Free Church of Scotland has intervened in the SNP's leadership race, accusing opponents of Kate Forbes of "anti-Christian intolerance."

The Finance Secretary - a member of the socially conservative church - has come in for criticism over her views on same-sex marriage, children born to unmarried parents, and issues around transgender women.

Ms Forbes was not a member of the Scottish Parliament when the equal law marriage was passed in early 2014, but has said that she would have voted no if she had been.

In another interview she said having children outside of marriage “would be wrong according to my faith.”

She also said she did not support self-identification for trans people.

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The comments - particularly those on same-sex marriage - led to a number of her backers quitting the campaign, including employment minister Richard Lochhead, public finance minister Tom Arthur, and children’s minister Clare Haughey.

The Free Church of Scotland said there was an undercurrent of "bigotry" in some of the criticism. 

In a statement, they said their congregation was composed of people "from all political persuasions, some of whom will not share Kate's politics, particularly over an independent Scotland".

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And it said it was concerned at the level of "anti-Christian intolerance which has been displayed on social media, and by some political and media commentators".

A spokesperson said: "It is lamentable that Kate's honest adherence to simple traditional values would, for some, disqualify her from contributing to the public good of Scotland.

"Kate Forbes is standing on the basis of her policies - the fact that she is being criticised for her Christian convictions shows a level of bigotry that has no place in a pluralistic and diverse society."

Asked about the fallout from the race, John Swinney told BBC Radio Scotland that the debate around Ms Forbes’ position had “absolutely nothing” to do with her faith.

He said: “I’m a man of deep Christian faith, but I don’t hold the same views as Kate has set out in the course of the last couple of days.

“I think it’s been unhelpful that the debate has been focused on the question of faith, because in my view it’s got nothing to do with faith.

“There are plenty of churches… the Church of Scotland undertakes same-sex marriage and I warmly compliment and congratulate the Church of Scotland on getting carefully to that position over some years.”

On Wednesday, SNP MSP Jim Fairlie said the way Ms Forbes had dealt with the questions had only strengthened his support for her candidacy. 

"If I am asked about my views on the issue of same-sex marriage or a woman's right to choose, I will defend them unequivocally without hesitation.

"I have two wonderful daughters, both born out of wedlock, and both now adults with their own views.

"On these points, Kate Forbes and I fundamentally disagree. But what we both agree on is that we are both committed to defending those rights.

"Therefore, we must also defend the right of religious belief. "

Mr Failie added: "I didn't support Kate for her religious beliefs, and I don't think her beliefs are in any way a danger to the LGBTQ community. If they were, I would not only withdraw my support for her, I would condemn her lack of tolerance.

"That is the main point for me. She has been totally honest in her beliefs, despite how difficult it was making her campaign, while at the same time defending the rights of others who are also trying to, in modern parlance, cancel her."

However, one SNP minister told The Herald: “It’s not about faith, it’s about basic competence and political leadership.

“You have only so much political capital to burn. So what are you going to use it on?

“Persuading the middle 20 per cent of voters to back independence, or mainstreaming the views of the Free Church?”

Another said they were surprised and disappointed at Ms Forbes’ performance.

“I thought she’d be savvier. She has such a lot of talent, but she’s f***ing it up.”