British broadcaster and survivalist Bear Grylls is well-known for pushing himself to the limits of human capability.

As the host of Man vs Wild, the former SAS soldier ate rotting zebra flesh, a yak’s eyeball and a live snake; fashioned a sleeping bag out of a camel’s carcass; and swam naked across a Siberian river in -67degC temperatures.

His tendency to drink his own urine as a survival tactic has spawned an entire meme format.

But ask Grylls the most difficult thing he’s ever done, and he doesn’t name-drop any of his stunts in the Sahara, the Arctic or the other extreme environments he’s conquered.

He says it’s writing a book – 2025’s The Greatest Story Ever Told, his immersive retelling of the life, death and resurrection of Jesus Christ.

Grylls’ biographical novel, which rose to the top of the Sunday Times bestseller list after last year’s release, is an account of Jesus’ life more akin to a thriller, and told from the perspectives of those who knew him best.

“I still  film our TV shows and I love all of that, but this has been different… It's been the hardest, but probably the best thing I feel I've ever done,” he told Petra Bagust in a Newstalk ZB interview that aired on Good Friday.

“Faith has always been a quiet part of my life… [but] the story of Jesus that I grew up with was such a sanitised version of it and never really felt relevant or personal to my life.

“As a teenager, when I eventually found a faith, it became a bedrock and anchor and backbone. I realised the real story of Jesus is so different from the one I grew up with as a young kid, which was very much rooted in church and religion – quite smiley and nice.

“The real story of Christ is so incredible and life-changing, and it's a story of courage, friendship, risk, rescue and sacrifice. I just thought so few people know that actual story.”

The Greatest Story Ever Told transports readers into the brutal realities of first-century Palestine and an unassuming refugee’s world-changing life and ministry.

Each character is assigned their original Aramaic names (Jesus becomes ‘Yeshua’, while Joseph is ‘Yosef’), with theologians and historians helping Grylls at every step of the writing process to maintain accuracy. Particular care was taken to ensure none of Jesus’ words were altered from original Gospel  accounts.

Grylls told Newstalk ZB The Greatest Story Ever Told is written for those without a faith, some of whom may not have had positive memories of engaging with Christianity in the past, to hear the Gospel story afresh.

“ So many of us with faith and religion, we have filters and bad experiences – and just the word ‘God’ or ‘father’ or even ‘Jesus’ can be difficult for people. We've done a pretty good job, over 2000 years, of screwing up a really beautiful ultimate message of love and forgiveness and redemption,” he said.

“That's why it's been so powerful for me to get so many letters, thousands of them every day… from every culture, every country, every faith – atheist, Muslims, you name it – all basically say the same thing, which is ‘I had no idea the real story of Jesus’.”

Asked by Bagust about the book’s connections to his adventure background, Grylls says the principles of survival on a mountain or in a jungle are much the same as when they are applied to the mental, emotional and spiritual challenges of everyday life.

“ These are part of our arsenal of weapons as a human. Look at the great stories of survival through prison or concentration camps or war or loss or whatever – that hope, that light, that spiritual bit is a powerful bit, [and] the physical follows,” he said.

“The great survivors have that burning light inside that is unrelenting and all-conquering, and it's what sets us apart as humans.

“ What helps me be strong in a jungle or a mountain? It's the same thing that helps me through the tough days of life. For me, my faith has … been that streak of steel. I don't want to stand on my own strength because a lifetime of surviving has made me realise I'm not that strong.”

Grylls’ favourite story from the book is when the Pharisees accuse Jesus of being a glutton and a drunkard because he’s affiliating with the rough end of society, and he responds by telling them he had come to seek and save the lost.

“I was one of the lost boys, I still am. But I was found – and I'm such a proud lost boy. I'm proud to be found. And that changed everything for me,” he said.

“I don't feel particularly religious. I don't go to church very much – I mean, I do try and go a bit with a family – but my faith isn't rooted in that.

“My faith is in the simple everyday: the connection, the friendships, the kneeling by our boys' bed before they go to sleep and saying a prayer for them. It's in laughter with good friends and love of family, and how we live and tackle risk and relationships and all these things.

“That's for me, how he [Jesus] lived and wanted to bring out that sort of spirit in us. He said, ‘I'm the bread of life, come to me’. I keep it simple, but that's how I try and live every day.”

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