If it’s 7am, the chances are Susan Brown will already be up and out the door. The moderator of the General Assembly of the Church of Scotland – and one of the very few women ever to hold the position – doesn’t like to pray in the traditional way. She prefers to have her conversations with God outdoors, on her long early-morning walks with her Labrador Finn. Does she always pray this way? Oh yes, she says, every day, even in driving rain and needle-sharp hail.

We shouldn’t be surprised. The moderator has spent most of her career in Sutherland, where driving rain and needle-sharp hail are frequent visitors, but some of her toughness probably comes from her family background too. She grew up in Penicuik where her dad worked seven days a week as a cage-man at the local coal mine, sending men down in the lift and then taking them up again. Money was tight. Attitudes were tough too, such as her mother’s view on Susan’s choice of career: the Church is no job for a woman.

As we know, Susan Brown ploughed on regardless, becoming the first female minister in Ross-shire, the first woman moderator of the county's presbytery, and then in 1997, when she was appointed minister at Dornoch, the first woman to take charge of a cathedral. The moderator is not, in her own words, a strident female who needs to be fiery about being a woman, but those are significant achievements; she was also happy to lead a procession in Edinburgh recently to mark the 50th anniversary of the ordination of women in the Church of Scotland. John Knox, she joked, would be birling in his grave.

Obviously, the moderator’s views on feminism matter: the numbers of male and female ministers in the Church are still a long way away from being equal – there are currently about 26 per cent women. However, Mrs Brown doesn’t much like the idea of targets or direct action. Some places will take longer than others, she says. It’ll work its way out in the end.

This approach is typical of the moderator’s pragmatic views. We talk about pretty much every issue facing the Church and on every one of them, she’s honest and realistic. She tells me about what the church should be doing differently – getting rid of a lot of its expensive buildings for example. She also talks about the absence of religion from schools and the effects it could have on young people. And she’s honest about the long-term future of the Church.

About religion in schools, she’s obviously worried. Mrs Brown did not grow up in a particularly religious family, but she did go to Sunday School, which led to Scripture Union and ultimately to the job she does now. I ask her if she’s concerned that those kind of structural links between young people and the Church – Sunday School, assemblies, school chaplains, etc – are going.

“Those structures aren’t just going, they’re gone in many respects,” she says, and yes, she is worried about it. “Parents want their children to have different choices and I understand that, but you can’t give children cold choices in the sense of just laying before them a whole pile of options – they need to experience what those options are and there’s a difference between telling folk things and actually letting them find these things out.”

For Mrs Brown, that means giving children an experience of church and religion when they are young and at school. “They have in fact fewer choices,” she says. “They have a greater knowledge of what faiths are about, but they have far less experience of any of them. It is in many ways a lost generation.”

Mrs Brown does recognise that there are greater social changes at work here. Earlier this month it was revealed that the Humanist Society now undertakes more weddings in Scotland than the Church of Scotland, which represents a monumental change. In 1975, the Kirk conducted 16,849 marriages, the largest number by any organisation. However last year, Church marriages were down to 3166, compared to the Humanist Society’s 3283.

However, the moderator bristles at the idea that humanist weddings and funerals are increasingly popular because they’re seen as more “personal” than church services. “The humanist claim is that theirs is personal,” she says. “Ours is incredibly personal in that you know the people and you give the stories of their lives.” She also says that in communities like hers in Dornoch, the church is still a part of people’s lives even if they don’t come on a Sunday. “In rural places, if you close a church, you’re probably closing the heart of the community.”

This is certainly how it was for Mrs Brown when she was growing up in Penicuik, where from a young age the church was central to her life. She grew up with a twin sister and an older sister and thinks Sunday School was a way for her parents to get some peace. Eventually, her siblings stopped going but she kept turning up.

“It just meant something to me and I would do it in a rebellious way,” she says. “Back then, you weren’t supposed to go to church in jeans so I would go in jeans. There was just something about it that always struck a chord with me – then, through Scripture Union at secondary school, it became vital – it was a need. So from 15, I felt the call to ministry.

“Did I hear a voice? No, I didn’t. Did I feel a very strong push, yes, I did. And that was at a time when I didn’t realise I’d never met a female minister. All the ministers I knew were men, but it didn’t occur to me that my sex was important or unimportant – I just felt a strong call and that was what I was going to do. My mum didn’t approve, which was the old-fashioned view that this is not what women do. I think that was the first time I thought: oh, somebody might not like this.”

She did think about doing other jobs – for a while, she considered joining the Navy or becoming a PE teacher ¬– but she’s 59 now and has been a minister for 32 years. More importantly, she seems to be enjoying it: famously, she was the minister who married Madonna and Guy Ritchie in 2000, but she seems to take the most satisfaction from the day-to-day ministry as well trying to do things slightly differently when she can.

Her theme for her year as moderator, for instance, is “Walking With”, the aim being to encourage walking as something that’s good for your physical health but your spiritual health too. As I’m leaving her office at the Church’s headquarters in Edinburgh, she presses a piece of wood into my hand and asks me to take it away. Carved into it is an impression of two feet - a reminder from the moderator that, although she’s just spent some time talking about herself and her work, the central focus is always the same: Christ.

One of the other new forms of ministry the moderator is keen on is social media, and, although she says she’s totally aware of its downsides, she’s finding herself doing much more counselling on private messaging and on Facebook.

Will it be enough, though, to encourage more people to join the Church and arrest the decline in congregations, which are 30 per cent down over ten years? The moderator isn’t sure but thinks part of the answer is to look at church membership in a different way. “It’s a radical thing to say but if you look at every organisation, from bowling clubs to brownies, they’re all on the way down – there seems to be a cultural fear of commitment through membership and we could find different ways of allowing people to be associated with a congregation or with the church. You don’t even need to use the word membership, you just let people be.”

The problem, of course, is that the church, like any other organisation needs money and “associate members” are unlikely to be a reliable source of it. I ask the moderator about all the big, expensive buildings the Church owns, including the one we’re sitting in on George Street in Edinburgh. Can the Church still justify all of this?

“I think we invest in too many buildings,” she says, “but those which are in the right place are useful and can be used for hiring out. The church has many buildings that it ought to be looking very seriously at and whether it needs them or not and that would be throughout the length and breadth of the country. We’re not using our resources responsibly if we don’t seriously stop and take stock of what we are, what we have and what we’re doing with it.” She indicates the building we’re sitting in. “There are lots of options on the table about this place – the fact that we are looking is the important fact.”

In other respects, the moderator is a little more conservative – she is cautious, for example, about new, more exuberant styles of worship demonstrated by the American minister Michael Curry at the wedding of Prince Harry and Meghan Markle and isn’t overly keen on touchy-feely forms of worship (“I’m Church of Scotland!”). She’s also clearly a home-buddy and, while she’s living in the moderator’s flat in Edinburgh, is missing the Highlands and her family – she has two grown-up children and is married to Derek, who is also a minister.

In other respects, though, the moderator is still a bit like the little radical that wore jeans to Sunday School, messaging her congregation on Facebook and promoting the ministry of the great outdoors. She is also utterly upbeat about the future of the church. Earlier this year, the Rev Dr Martin Scott, the Secretary to the Council of Assembly, said the fall in congregations, and the effect on finances, could mean the Church ceasing to exist within 30 years, but the moderator is having none of it though.

“There is no way that, after 2000 years, the church is going to cease to exist,” she says. “It may change shape and form, it may dramatically turn around and look very different, but it isn’t going to cease to exist.”