Britain's main liberal party is probably about to elect an evangelical Christian as its leader. If you're someone who follows US politics, you may want to read that sentence back a couple of times to check you got it right.

There is a widely used narrative (inspired by one particular mix of theology and political ideology popular in some parts of America) that liberals and evangelical Christians are at opposite ends of the political tug-of-war: straining every sinew to move things in precisely the opposite direction from each other. The narrative has the strength of dramatically setting up a culture war between two enduring and popular ideologies. It has the weakness of misunderstanding both liberalism and evangelical Christianity.

In a recent blog series on 'Faith at the Ballot Box', Claire Mathys, director of the Liberal Democrat Christian Forum, was asked what accusation levelled at her party she found most frustrating. She didn't talk about misrepresentation of the Lib Dem's power in the coalition, or clichés about its members. Instead, she was frustrated by how "some people think that the Liberal Democrat Party is a secular party and not the home of many Christians." She added that in a recent survey more than a third of party members said they went to church regularly. Before the election around a quarter of Lib Dem MPs were Christians; now four of the party's eight remaining MPs identify as Christians. Mathys also pointed to the book written by Christian politicians in the party: Liberal Democrats Do God. It's clearly an accusation she's tired of hearing.

Enter Tim Farron.

You would do well to find a public figure who will more passionately and articulately talk about their faith. Farron became a Christian aged 18, a decision he describes as "the most massive choice I have made," and his faith seems as powerful and fresh as ever: Speaking at the National Parliamentary Prayer Breakfast in 2013, he said: "Christianity, I am convinced, is not 'a bit' true. It is either not true, or it is so compellingly utterly true, that almost nothing else matters...if it is [true], it's the most important thing in the universe bar nothing; and if it isn't, we should close all the churches and sell them off for something else. There is no middle way."

But rather than the 'holier than thou' stereotype of some Christians who raise their faith in the public square, Farron is clear that Christians are no better than other citizens: "Christians aren't good people...Christians are people who have worked out that they're not good people."

Farron is also clear that his Christian faith is not simply private and personal, since he believes that the Christian gospel is true, he wants others to believe it too. He closed the same meeting by challenging the assembled MPs and Peers, saying: "What I want to encourage you to take away today is that the Bible might be massively confusing, hugely challenging, [with] bits of it you might find hard to believe – but there are four or five days in Jerusalem, 2000 years ago, the evidence for which is staggeringly compelling, and if it's true: everything – everything – changes."

At the same time as all this, Tim Farron is a leading star of the Liberal Democrats, enjoying enormous popularity among the party's members (not least because of his opposition to the rise in tuition fees, which he described as a matter of integrity). Between 2011 and 2014 he was party president, and he is now the clear favourite to be elected its new leader, following Nick Clegg's resignation. Only 24 hours after announcing his candidacy for leader, he already boasts the endorsement of the Liberal Democrats' leader in Scotland, its leader in Wales, and a number of former and current MPs, as well as hundreds of people who pledged their support online, while #tim2lead trended on Twitter. There's still a whole campaign to go, but things have started well.

But if the popular narrative is to be believed, Christianity and Liberalism are enemies, not bedfellows. So how does Farron identify as both, without leaving his faith at the door of the House of Commons? As ever, Farron's answer is honest and eloquent: "the danger is sometimes that as a Christian in politics you think your job is to impose your morality on other people. It absolutely isn't."

He quotes the Welsh preacher Martin Lloyd-Jones, who said that a Christian's job "is not to reform society but to preach the gospel". Farron added: "What he meant by that is that you don't create Christian institutions and impose them on people who are not Christian. That is illiberal and it's counter-productive. But if you can convince people of the gospel, people will change their lives... Edmund Burke once said, 'all the laws against the godless have not saved one single soul' – and so we are wrong if we think our responsibility is legislate to make this a more Christian place."

Rather, Farron sees that his responsibility, as a Christian with increasing prominence, is to "make the case for Christianity, and give people a chance to take it more seriously and look into it for themselves." Some Christians may disagree with him on these points, but it is very clear that Farron's position is rooted in firm principles, not comfortable compromise.

It's become obvious in the aftermath of the election that many of us, especially those of us who use social media, are not very good at empathising with the variety of political views that there are in the UK. That's certainly true of Christians. As any Christian working in politics, of whatever party, will tell you, it's not long before you'll be asked "How can you be a Christian and vote for them?"

Thankfully, in the election campaign, many Christians of different political views came together to argue for their parties in a way that encouraged people past this kind of simplistic partisanship, and showed that faithful Christians can mix faith and politics in a variety of weird and wonderful ways – whether Conservative, Liberal or whatever. If Farron becomes leader, maybe even the wider media will be persuaded to finally reject the old, broken 'Evangelicals vs Liberals' narrative too.

Johnny Monro works in Parliament as a researcher and speechwriter.