When my friend was struggling with alcohol, and trying to find meaning in existence, he used to seek out the company of a Free Church of Scotland preacher.

At first, I was baffled. This preacher held retrogressive beliefs which were at odds with my friend’s, and he disapproved of my friend’s choices.

But then it occurred to me: for all his judgement, the preacher made time for my friend, even when he was at his lowest. Whereas others, who espoused more liberal values, would cross the road to avoid him.

This is not a defence of narrow values, nor of Kate Forbes, whose failure to embrace equality or to adequately separate Church and State should, I believe, preclude her from leading any political party, and especially a party which so self-consciously brands itself as progressive.

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It is merely a recognition that life can be complicated and that there is more than one way to practise (or not practise) what you preach. 

That senior politicians continued to tout Forbes as a potential successor to Nicola Sturgeon, despite knowing of her beliefs, suggests her adherence to the diktats of the Free Church did not impact on her everyday dealings with her colleagues, and so could be put in a box marked “Kate’s quirks” .

More cynically, it suggests they assumed she’d have more nous than to lay out her prejudices for public consumption; that they expected her to prevaricate as is the political norm. 

When she refused to do that, freely admitting she would have voted against same-sex marriage in accordance with her religion, they turned against her so quickly it was borderline cruel. John Swinney did so while referencing his own “deep faith”, though it might have been more charitable - more Christian, even - if he and others had told Forbes they considered her views beyond the pale before she put herself up as a candidate.

The Herald: SNP leadership contender Kate Forbes is a member of the Free Church of Scotland

While the scrutiny of her religious beliefs is legitimate, It has been painful to watch. Though not as painful as it has been for the targets of her bigotry to hear her undermine their existence.

The whole affair has damaged the self-image of the party, too. And yet it has provided an interesting insight into the place of Christianity in our increasingly secular society. Talking about God makes most people uncomfortable. An easy, kneejerk approach for sceptics is to dismiss believers as deluded idiots investing in fairytales. And yet the search for meaning and spirituality is a timeless human impulse.

Most believers I know are not slavish devotees, but profound thinkers who reflect on what faith means in the 21st century. They may cleave to a particular Church - for its community or out of habit - but their understanding of, and their relationship with, their God, is a personal matter, separate to that Church’s doctrine.

Fundamentalists may deride this as “pick and mix”; but it makes sense in a world that has largely moved on from Old Testament scourges and smitings.

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As Green MSP Ross Greer said, if your conception of God is as the embodiment of love, you are not going to buy into Him/Her hating on the people - male or female, straight or gay - that He/She created. 

Forbes’ unwillingness to separate herself from the tenets of the Free Church - even when it comes to legislating for Scotland as a whole, and even if it wrecks her shot at the leadership - is what shocks. But it also shines a light on others’ willingness to bend with the wind; and their slipperiness when challenged on their own positions.

Take Humza Yousaf. He, too, is a man of faith, a practising Muslim. Islam, like some branches of Christianity, continues to consider homosexuality as a sin. Yousaf says he supports same-sex marriage.

He voted in favour of the general principle of the bill, but missed the final Stage 3 vote. He has always insisted his absence was due to an “unavoidable clash”. But last week Alex Neil, the cabinet secretary who took the bill through the Parliament, claimed Yousaf arranged the meeting 19 days in advance because he was coming under pressure from the mosque. Neil may have his own agenda.

The Herald: SNP MSP Ash Regan resigned as Minister for Community Safety before last Thursday's vote on the Gender Recognition Bill (Photo by Ken Jack/Getty Images) (Photo by Ken Jack/Getty Images)

Still, if there is any truth to this, it suggests Yousaf’s commitment to same-sex marriage is not as unwavering as he has implied. Or at least, that he is not prepared to defend it at any cost.

Meanwhile, Ash Regan has been trampling all over the moral high ground. She posted “Love Is Love”, while defending Forbes and calling on others to “end the mud-slinging”. But then it emerged she had brought mudslinger Kirk Torrance onto her leadership election team, and attempted to run away from Channel 4 journalist Ciaran Jenkins’ questioning.

Torrance once suggested the Alex Salmond court case was a “stitch-up” and said Sturgeon was “up to her dark eyes” in it. He is a former Alba candidate. Regan was also photographed alongside Robin McAlpine who resigned as director of Common Weal after writing an article in which he said Sturgeon “developed and executed in secret” a “coordinated plan of action” to drive Salmond out of politics.

Regan is presenting herself as the “unity” candidate but there are certain people one wouldn’t want brought in from the cold. Nor does baiting the Greens seem like a hand across the divide.

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With Forbes, what you see is what you get. Which is perhaps why on Friday morning, despite the carnage of the previous few days, a poll of SNP supporters (not members) put her in the lead, eight points ahead of Yousaf.

In terms of competence, Forbes would be my preferred candidate; but the leader of a party is the symbol of all that party stands for. And what the Finance Secretary stands for is a world in which some people are more equal than others. Not only does she believe that same-sex marriage is wrong, she would, given the chance, have forced others to live by those beliefs.

Her insistence she will not roll back on existing rights has not yet been stress-tested, and we have no idea how her religion would impact on issues such as assisted dying or the introduction of buffer zones around abortion clinics.

Yet Forbes' beliefs are not the only unpalatable ones on display; and the stoking of a gratuitous religious backlash, by the likes of Douglas Ross, can only foster greater division. Nor do the other candidates inspire much confidence. Yousaf did not shine as justice secretary and has gone on not shining as health secretary.

The Herald:

Regan’s only real locus is as the pro-same-sex marriage, but anti-Gender Recognition Reform bill candidate (with added Alba-appeal).

As far as it is possible to decipher, her unsustainable belief is that she alone can deliver independence thanks to a superpower that will force the recalcitrant UK government to bend to the SNP’s will.  Regan's values seem askew, too.

Where Forbes has been criticised for prioritising her religion, she says she is  “a mother first and a politician second”  in an attempt to justify sending her children to private school.

Of course, along with most of the rest of the country, I don’t have a vote. The all-but 104,000 of us who are not SNP members can only stand and watch as the party of government trashes Sturgeon’s legacy before she even leaves Bute House; as its different wings fight over gender and LGBT equality, while, all the time, socio-economic inequality goes on deepening.

With no Scottish elections due until 2026,and no prospect of the SNP calling a snap one, we will have to thole whichever candidate comes out on top. Or, as seems more likely right now, whichever candidate comes out the least damaged.