Alan John Miller was in his early 30s when he started wondering whether he might be Jesus. Throughout his life, he says, he'd dealt with a series of inexplicable memories and holding them back was just getting harder and harder. "I had memories of somebody putting nails through my feet and through my wrists," he says. "I remember being speared, being threatened, and being beaten on a number of occasions almost to the point of death."

But it wasn't the cult thing that captivated me. I just kept wondering what it's like to come out as Jesus. What level of self-assurance is necessary to look a friend in the eye and say, "So look, mate, this might sound weird, but I'm Jesus." Because regardless of who you are, or what your motivations, rebranding yourself as a first century prophet equals social suicide. And yet Alan pushed ahead anyway, as did Mary.

This is when I first learned about Alan, watching Channel 7's Sunday Night. I saw this guy in a floral shirt sincerely explaining he was Jesus of Nazareth, while his girlfriend declared she was Mary Magdalene. There was also footage of barbed wire fences around the couple's compound, and interviews with people who'd gravitated from around the world to live with them. This interview attracted a lot of press, and 2012 snowballed into a big year for them. The Sydney Morning Herald published a feature titled " the Messiah Complex ," while a Current Affair basically cleared their schedule to run Jesus updates.

It took another decade for Alan—a former Jehovah's Witness and divorced father of two—to finally decide he definitely was Jesus. By this time, he was 41, living alone on the South Australian coast. Working as a computer technician with a successful business and two teenage sons, he knew presenting himself to the world as Jesus would make a mess. But he did it anyway. And he did it with such conviction that some seven years later, in 2011, he was making international headlines as an alleged cult leader.

I wanted to ask them both about the nature of self-belief, so I decided to travel to Queensland and meet them at home.

From a nearby building, Jesus appears, wearing another of his trademark surfer dad shirts. His accent and mannerisms are pure Australiana, and we make easy chat about the drive as he shows me around the property. We enter a house to find four people seated at a dining room table, including one of Jesus' sons and his partner Mary. We all shake hands before I excuse myself for the bathroom, only to find a copy of Richard Dawkins' atheist classic, the God Delusion lying on the floor. It's amusing enough to take a photo, and suddenly I relax.

From their rural home in Wooroolin, about three hours north-west of Brisbane, Jesus and Mary run an organisation called Divine Truth —distributing hundreds of hours of YouTube presentations, with such hooky titles as Enforcing Love and Truth, and Facing My Resistance to Truth. It's a long drive there, but it's only as I turn off a gravel road and into a property of trees and sheds that I suddenly get nervous. I'm alone and I have no idea what I'm in for. So at the last minute, I decide to park the car pointed towards the road. Just in case.

"Well, I knew there were four options," he says slowly. "I thought: Either I think I'm Jesus and I am, or I think I'm Jesus and I'm not, which would make me crazy. Or I think I'm Alan John Miller and I am which would make me sane. Or finally, I think I'm Alan John Miller but I'm not and that would make me crazy."

After that we get down to business and move over to their studio, where the couple shoot the bulk of their video content. It has a three-camera setup with lighting, as well as extensive post facilities and a mixing desk. I sit in a big chair, lights on me, and Jesus sits in the chair opposite, and throws a leg out so Mary can sit on his lap. Then I ask Jesus to take us back to that time when he was living alone in South Australia, deep in the throes of an identity crisis.

Feeling encouraged, he started telling a few friends, but most were outright hostile. They all insisted he was crazy. Within a month, people stopped returning calls. His own mother told him him to go see a psychologist. He did, but the results came back non-conclusive.

Jesus admits it was the idea of trying to explain this to people that terrified him, but he eventually decided to try it out first on his teenage sons. "I told them in a 'what do you think of this?' kind of way and my youngest son actually said, 'Yeah I can see that.'"

This part of the story gets messy, because it's difficult to understand how Mary Luck so completely reinvented herself without being pushed. She's aware of this, and reiterates several times how it was all her own choice. For some reason, I find myself believing her. Out of the two of them, Mary seems the more relatable. While Jesus seems to jump between two characters that I'll call Laconic Bloke and Unblinking Messiah, she just seems to be herself.

With his friends gone, Jesus felt ironically liberated to embrace his new persona, and began giving public talks around the country. This was how in late 2007 he found himself in a Queensland living room presenting a talk to a 28-year-old occupational therapist and her parents. The woman was named Mary Luck. Her parents were self-described atheists, but they found these philosophical sermons on the nature of truth and love from a computer engineer who called himself Jesus all very interesting.

She laughs easily. She gets embarrassed easily. She says that she used to be the girl who went out with friends and insisted on cocktails. I can picture that clearly, even if she then describes a void that she couldn't fill without Jesus.

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For as long as she could remember, Mary says she felt uncomfortable just like Jesus. She describes a deep sense of loss, as though she'd loved someone who had died. Her family were emotionally reserved, and she lived through periods of depression alone—until this guy showed up in her house with his own theory about what was happening to her.

After that first meeting, Jesus ended up telling a friend he thought she was Mary Magdalene. Eventually this got back to her parents who told her. At first, she was shocked but still decided to email him. "I said, 'look I've heard something about what you think about me, but I'd like to hear it from you.' That was all I wrote."

Jesus told Mary they had known each other for thousands of years, and that their separation explained her feeling of loss. He suggested they should get back together, and although it took her a long time to reply, she eventually did. And even though there's a 15-year age difference between them, they slowly grew closer. And slowly she came to believe that she just might be Mary Magdalene.