I was in Tim Farron's constituency at the weekend. It's arguably the most beautiful place in England. Standing by the banks of Windermere, one feels a long way from London.

In the wake of Tim Farron's resignation, there appears to be a similar gulf between his interior world and the harsh reality of Westminster politics.

The tidal wave of comment after his resignation as Leader of the Liberal Democrats has brought a very unfashionable concept – sin – back into the national conversation. But has it been given a contemporary twist. 

It's almost exactly 50 years since the passing of the Sexual Offences Act which decriminalized homosexual acts between men over the age of 21 (and which was supported and aided by some in the Church hierarchy). Since then gay rights have advanced rapidly while at the same time, the culture has become markedly less 'Christian' in its discourse.

One of the most telling elements of the whole saga of Farron's demise was the way in which his personal views of sexuality (and, to a lesser extent abortion) have been portrayed. From the time he took the leadership of the party, almost two years ago, his views have been interrogated on the basis that he viewed gay sex as 'a sin'.

'Personally, though, do you think, as a Christian, that homosexual sex is a sin?' asked Cathy Newman of Channel Four News in July 2015. This set the tone for questions the Liberal Democrat leader would face throughout the next two years, but especially during the 2017 election campaign.

Newman fired the starting gun again, in April 2017, 'A while back I asked you whether it was true that you believed homosexuality was a sin and you struggled to answer. Now you've had a while to consider that question, what is the answer?' she asked.

On both occasions and in subsequent grillings across the media, Farron's answer was fairly consistent. It essentially boiled down to the idea that he was a true liberal – he didn't want to impose his view on anyone else – therefore he should be judged on his record, not his personal opinions.

Here's where things get interesting. In a post-Christian country which has a Church attendance rate of around 10 per cent, it's clear that most people don't have a detailed concept of what 'sin' actually is. Yet it was Farron's belief (or not) that homosexuality was a 'sin', which brought down opprobrium on him.

In his remarkable book about the Christian faith, Unapologetic, Francis Spufford ruminates on how 'sin' has become a deracinated concept in the UK. He amusingly recounts how we have left behind the concept of sin to such an extent that it's now used to advertise a number of 'naughty but nice' products. 'Case in point,' he writes 'the word "sin", that well-known contemporary brand name for ice cream. And high-end chocolate truffles.'

Tim Farron was repeatedly asked whether he believed gay sex, or merely being gay, was 'a sin'. The secular media which had him under the spotlight doesn't understand Christian faith very well. Religious literacy among the UK media is, with some honourable exceptions, pretty poor. The end result was Farron being criticised over sin – in spite, presumably, of most of those asking not believing sin was an actual thing.

In the heat of the campaign, under serious scrutiny he eventually said, 'I don't believe that gay sex is a sin... if people have got the wrong impression of what I think about on these issues, then that's something it's right you correct.'

A great number of commentators dismissed him as a bigot on the basis of a category (sin) that they don't believe in.

Or maybe they do? Maybe every society does believe in sins, even if it doesn't call them that.

There are positions which can't be transgressed without putting yourself outside the mainstream. Today, at least in parts of the UK, it seems it is essentially a sin – a grave wrong – to express dissenting views on sexuality. Tim Farron may have found that out to his cost. Previously acceptable views on race and gender have been consigned to the dustbin of history in polite society and now it seems we are at the same point with sexuality.

None of this is to say that Farron is right or wrong in his views or his decision to resign. That he did so on the basis of his personal view of sin, though, is significant. In the 1950s as the country began to wrestle publicly with the issue of legalisation, the Church of England Moral Welfare Council issued a statement that said, 'It is not the function of the State and the law to constitute themselves the guardians of private morality... to deal with sin as such belongs to the province of the Church.' It seems now that as well as the Church, the court of public opinion, via the media, now plays a role in it too.