His parents handled it with grace, Dave says. But that wasn't enough to lure him back to the fold -- not yet, anyway. More fighting, boozing and womanising lay ahead. The teen pregnancy was just the beginning of Dave Jensen's unholy adventures.

Fast-forward 20-odd years and Jensen, now 42 and an evangelist preacher, is posing for the Herald's photographer at St Stephen's, Newtown, not far from the Anglican seminary Moore College where he grew up, and his father taught for more than 20 years.

His journey is plotted in ink on his muscular arms, which are folded over the pew in front of him.

The wilderness years are represented by a portrait of a winged St Michael -- the kind of image that only someone who has wandered away from the cerebral, iconography-shunning Sydney Anglicans would choose.

I ask if it's the archangel. "Maybe?" he says. "I'll have to Google. I chose it from a [list of pictures on a tattoo parlour] wall."

St Michael has since been joined by tattoos more aligned with Sydney's orthodoxy.

John 3:3 is written on his wrist, and there's a quote from John 1:14 -- "we have seen his glory" -- inked across his chest. Those came after what Jensen describes as his true conversion to Christianity as an adult; after the prodigal son returned to the fold.

Jensen was always, technically at least, a Christian. As the son of Australia's most influential Anglican family of the modern era, he had no choice.

His father was archbishop, his uncle Phillip -- an outspoken character who once described Catholics as "sub-Christian" -- was dean of St Andrew's Cathedral, and his eldest brother, Michael, is now the rector of St Mark's, Darling Point.

Peter Jensen's mark on the church is indelible and controversial. He fought against the ordination of women -- "within the family, men are the spiritual guides" -- and made it the diocese's explicit mission to have 10 per cent of Sydneysiders in Bible-believing churches.

He was a founding member of a Southern Hemisphere Anglican coalition that effectively split from the Archbishop of Canterbury because it felt the Europeans did not follow the gospels faithfully enough, and has driven a fracture in the domestic church over same-sex blessings.

"His legacy holds firm," says Muriel Porter, author of The New Puritans; The rise of fundamentalism in the Anglican Church. "Sydney diocese is a more conservative place than it was when he was elected two decades ago, and the national Anglican church is now completely dominated by its representatives."

So if anyone was going to be born a believer, it was the youngest son of Peter Jensen. "My mum and dad loved Jesus," says Jensen the younger. "We'd eat dinner as a family and we'd read the Bible together every night. We'd pray after dinner as a family."

He always believed Christianity was "probably true". But it was an abstract thing for him, not the all-consuming passion it was for other members of his family, including his twin sister. "I hit a point in my teenage years where it was just no part of my life."

As a teen, he didn't tell his family about the girls and the drinking and the "occasional drug use ... I just lied about it". The pregnancy forced his hand. His mother banged her head on a pantry door and then sat down and asked how she could help.

"My parents were endlessly gracious," he says. "There wasn't a single moment of, 'Oh, I'm the Archbishop of Sydney'."

The young couple wasn't forced to marry, but did anyway. Jensen had dropped out of university and was working as a furniture removalist when he saw an army recruitment ad on a bus. He went to officer training at Duntroon, then moved to Townsville with his young family.

He was faced with a series of moral choices in the army, and Jensen is the first to admit he made poor ones. He was a 20-something in charge of blokes who'd fought overseas. "They'd call you sir, but they'd say it in such a way that you know they mean ...

"You've either got to be exceptionally competent to win their confidence," -- he says that he wasn't -- "or try to be their friend, which never works, or you try to out-drink and ... out-macho them. I threw myself into drinking ... you're in a drinking, womanising, violent culture."

He was in his early 20s when his marriage ended in divorce. He took the opportunity to indulge further in what he says was ego, selfishness and a desire to be admired. He got buff, played footy and partied hard. "I was a very good drinker, I was very violent, I was constantly being arrested and put in the drunk tank for fights in the street," he says.

"Lots of womanising. Like everyone else I knew, I looked at pornography. I wanted to be liked and admired and respected. I'd lie about my background. I was proud of my dad, who was archbishop at the time ... But I wouldn't volunteer that information."

He was 28 and a captain living in Darwin when he watched a few sermons his sister loaded onto a laptop she'd given him. "I woke up one morning and for the first time ever I stopped to think about my life," he says. "I'm living, but I have no compass."

He rang the army padre, who'd studied at Moore College when he was a kid. They began talking. And talking. He began going to church after big nights out. It was like jigsaw pieces coming together. Twenty-eight years after he was baptised, he converted.

"It made sense of my life," he says. "I'm utterly convinced it's true. Not just because my dad told me. I discovered it for myself."

I asked if his parents were thrilled when he returned to the fold. "It's safe to say they were," he says, but adds that they had never been judgmental, not even about his divorce; "not one, 'oh you're an embarrassment'. Not one, ever".

They see life, he says, from an "eternal" perspective.

Fast-forward 14 years, and this prodigal Jensen is following in his family's footsteps with a high-profile job in the Sydney diocese, which involves itinerant preaching and working as an evangelist, or, more simply, in Christian recruitment.

He's regarded as having particular expertise in the attitudes of the less faithful because he was one of them for so long. His second wife, the mother of his four sons, is also a later-life convert; she was a Catholic barmaid and spontaneously popped into a "Bible-based" church one evening. "She'd become a Christian," he says, "about a year before me."

Jensen is not an ordained minister but says that's not due to his divorce, which can be a road block to advancement at Sydney Anglican, but rather to his failure to meet Moore College's high academic standards. "I'm a terrible student," he says.

He admits that reaching out to non-Christians can be a hard road. There are plenty of brick walls. It can be a thankless task. "None of us like being hated," he says. "And ashamed. None of us enjoy feeling rejected. But Jesus is clear, he wants us to tell people about him. He also promises us it's going to be really hard and difficult."

Jordan Baker is Chief Reporter of The Sydney Morning Herald. She was previously Education Editor.