Image caption The Caudle family are well used to religious debate

The UK is now more religiously diverse than ever but at the same time the number of people with no religion is at an all-time high. So how do you deal with your partner's faith in God if you don't have it?

"I'm a confirmed atheist, I'm a born again atheist, basically I make Richard Dawkins look a bit undecided."

Jez Caudle, 44, is more than clear about his beliefs - or lack of them. He lives in Camberley, Surrey with his wife Heather and their two boys William, nine and Kenny who is six.

Jez didn't know Heather was especially religious when they met - he says it was only when they moved in together and she started going to church more that it became clear she was a practising Catholic.

Find out more You can listen to the full Asian Network documentary about mixed-faith relationships - For The Love of God - on BBC iPlayer

Now, their children have been baptised. Jez supports them attending church every week despite not wavering at all in his fervent disbelief, which makes for plenty of debate in the household.

William will happily sing hymns, yet like any child he's picked up on his father's cynicism. Preferring to play on his Xbox, William refused to go to church recently saying religion was "a load of rubbish" but then changed his mind - now he says he believes in God but it upsets him when mum and dad row about it.

And then there is the small matter of what happens after this life.

"She has mentioned it a couple of times and I think she worries about that, that we're not going to be together in the afterlife," says Jez.

Media playback is unsupported on your device Media caption Tauseef's story: I want to convince my wife I'm Muslim enough for her to be okay with me

"But, as I'm not having one," he shrugs, "I can only go to hell, by her set of beliefs, if her religion is the true one."

Heather is more hopeful. She says she sees it "as part of her duties as a wife" to pray that Jez gets into heaven and she quietly hopes that one day he will change his mind anyway and accept God.

He thinks the same - that one day she will wake up and realise there is no God. Both say that's not going to happen.

The issue of the afterlife comes up again and again with these sorts of relationships - mothers who don't think their agnostic children will be in heaven with them, and for one wife, the belief that her place in hell is now decided by her husband's rejection of God.

Image caption Tauseef says he pretends to be Muslim to appease his wife

Tauseef is that husband - though his name has been changed because his Muslim partner doesn't know he is being interviewed.

"It's a massive sin for her to knowingly be with someone who doesn't believe and she knows that," he says.

Tauseef grew up Muslim but, by the time he was 15, had become an atheist. He still ended up marrying a Muslim - but he says she was less practising when they met.

The couple are both British Pakistanis and he hoped their similar cultural backgrounds would be a good thing. That religion would come second to this - and to love. "Perhaps we were a bit naive," he adds.

Tauseef agreed to make some changes - to not drink when he was with his wife and to accept she would be in charge of the religious education of their children. But she grew more religious and he didn't - despite trying. He now finds himself pretending to be a believing Muslim to appease her.

"She wants a husband who will take her on Hajj [the Muslim pilgrimage to Mecca] and lead her son in prayers but she knows I'm not the person to do that."

"Three or four years ago I was serious about trying to find my way back into the religion as insane as it sounds," says Tauseef. "I hung around with people who were more religious, I joined forums but deep down it was impossible and I was just kidding myself."

"Now I've given up. I'm more inclined towards convincing my wife I'm Muslim enough for her to be with me."

Tauseef is willing to lie, to bring up his son as Muslim despite not agreeing with the religion or the lifestyle he says it dictates, and also to live a double life if he gets to keep his wife.

He recently got caught out by drunken photos on Facebook after telling her he could never touch alcohol again. He ended up sleeping in a different bedroom, with his bags packed but says he won't give up because of their son. "I'm still in love with her but I'm pretty sure she isn't, she makes that pretty clear."

Even when both people in a relationship are in love with each other, there are other challenges to deal with, especially if you're gay and religious, but your partner isn't.

Image caption Glyn (right) doesn't rule out ever changing his faith

That's the situation for agnostic Glyn who lives with his husband David in east London. David is an Orthodox Jew and while accepting that his gay relationship doesn't sit entirely with what some would consider orthodoxy, he lives largely by the rules of his religion. On a basic level Glyn is responsible for keeping their kitchen kosher, dividing the small room into meat and dairy and keeping some of his favourite food well out of it.

"I do have pizza delivered and I just sit there and eat it in the box in the living room and wash my hands afterwards. It certainly can't come into the kitchen or go in the oven that's for sure."

David observes the Sabbath - he won't travel on a Saturday or use electricity and so the couple can't socialise on that day. Glyn admits that some of the adjustments have been a little awkward, others a little strange, especially as he doesn't believe in them.

"Particularly Passover. The ultimate part of it was me coming home from work one day and finding practically most of the kitchen had been covered in tin foil to avoid contamination - which I think I took fairly well."

Image caption On their wedding day

"There are times I think, 'oh my gosh, this is driving me around the bend'. I have had to make bigger changes but David's faith is very important to him."

Glyn doesn't rule out ever changing his faith, but David has never asked him to. He says he prays for Glyn but doesn't concern himself too much with others people's faith. The couple don't plan to have children and admit that makes things less complex in many ways.

For Heather Caudle, the children still pose a question. While they grapple with mum and dad's opposing views, she knows there is a danger the confusion won't lead to God.

"My worry is that they become atheists. Because that's just two more people to pray for."

Interfaith marriage in the Census

In the 2001 Census 20,635,298 were recorded as married

Of these 882,007 were in a mixed-marriage, in which both partners come from one of the following groups - no religion, and Christian or Muslim and Sikh

The most common combination by a long way was Christians married to those of no religion at 749,782

The next most common combination was Muslims married to Christians at 21,396

There were 13,457 Christians and Jews married, 336 Muslims and Jews

Figures for mixed-faith marriages have not been collated for the 2011 Census, though groups who support couples report anecdotal evidence of an increase

According to the 2011 Census four out of 10 people with no religion are aged under 25 and four in five are under the age of 50

You can listen to the full radio documentary about mixed-faith relationships - For The Love of God - on BBC iPlayer

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