"The concern for voters would be that such a person would have their allegiance to the Church and not to the SNP. It is one thing to bring your religious beliefs to politics, but it is another to bring the dogmas of a right-wing Catholic organisation. That would be the worry for voters."
The HSS will argue that this only applies to members of Opus Die but their wording and the title of their society would point to their underlying agenda.
In 2005 I faced Michael Connarty a well known MP in the British Humanist Society. He is well aware that I was one of two of his opponents in that campaign who confessed a Christian faith. But I'm sure that if you were to ask Michael should that disbar me from seeking election to the commons he would say of course not. The only thing he would argue that should prevent me from sitting in the House of Commons are my views on policies.
Indeed many of my secular friends feels that surely my faith must shape my politics, while many of my Christian friends accuse my politics of affecting my faith. I guess somewhere in the middle is where the truth lies. Indeed if you were to look at my voting, speaking and writing record I'm sure you would be hard pressed to guess or prejudge just how you'd expect me to react based purely on my faith. Indeed I did blog against a lot of fellow Lib Dems on the matter of how liberal are we on the matter of people's believes over some of the clamp downs on religion in recent months.
If we are to have a representative democracy part of that democracy must still be those of faith, all faiths in our country. Yes some of them will have very conservative views on a number of ethical matters, but not all people of faith are that bound by that when they come to matters of conscious. Charles Wesley was actually under fear of personal assault when he preached from the pulpit to end slavery for example. There are Christians on both sides of the debate regarding human sexuality and abortion for example. It is not just as black and white as the NSS would maybe want to have us believe.
No doubt this may spark some debate from the usual quarters, but we can't go blocking people from seeking election for any reason we just don't happen to agree with. If they are way out of line then we need to win the debate, show them up for what they are. But merely being of faith is not one of those reasons. Many of those as Simon pointed out were actually at the vanguard of social reforms going against the norms of society. Don't forget it was son of the Manse David Steel who he introduced his Private Members Bill in 1967 to legalise abortion, although Roy Jenkins had wanted him to sponsor a bill on homosexual law reform to incorporate Scotland when he came up in the ballot. So the NSS and others shouldn't tar everyone of faith with the same brush, sometimes we're the most revolutionary, forward-thinking, risk-averse people out there.
* UPDATE: Correction has been made as I originally posted Human Secularist Society instead of National Secularist Society. There may have been some confusion with the Humanist Society of Scotland who have made no statement on David Kerr.