Destiny Church head Brian Tamaki has been in hospital recovering from serious burns to his face and body after a rubbish fire went horribly wrong.

Tamaki preached to his church congregation yesterday for the first time in weeks, and told them he had "been through a fiery furnace and out the other side".

His wife Hannah told the congregation she could easily have been a widow after the accident, which happened in late March.

Burns were still visible on Tamaki's hands during the sermon yesterday and he said he had lost weight. His voice was also slightly damaged, he said, from "literally" breathing fire.

"I can still smell the smoke... I got burnt to 30 per cent of my body. Second-degree burns," he said,

"I got tired of looking at this rubbish and I thought I'd quickly burn it before I go away. And things evolved from there."

All except his torso was burnt in the accident, he said.

"I endured a lot of pain, but also a lot of interesting things in that time," said Tamaki, who told the congregation he had written a book about the experience called Living in the Light of Eternity.

His face was badly burnt, he said, but he was told that the process would be like a "chemical wash" or peel which would leave his skin smooth like a baby's.

Tamaki said he still could not go out in the sun after the accident because his skin was sensitive.

He thanked the hospital staff who had helped him heal but also attributed his quick recovery to his healthy lifestyle and positive thinking - "not cursing my crisis but looking to what can I get out of my crisis".

Hannah Tamaki became his nurse. She said he was a difficult patient at times but "God will never put you in a situation you're not capable of handling".

The accident happened four days after their wedding anniversary, which is March 22.

"We were praying and I said 'Let's pray against the spirit of death. There's a feeling, I don't like it. We prayed together against the spirit of death.

"Little did we know that four days later I could have been a widow today - honestly, that's how serious it was."

The Destiny Church founder's ordeal had been kept quiet on social media because she had told people she would "smack their bottom" if they shared it.

Tamaki tweeted about his support for Israel Folau last week after the rugby player told an Instagram follower gay people were destined for hell.

READ MORE: Brian Tamaki tweets support for Folau's homophobic comments

Tamaki had stayed silent on the subject because he was still in recovery, he told the congregation. He had waited in vain for other Christians to step in and show their support for Folau.

Tamaki said it was the "duty of any hot blooded Christian" not to back away or criticise fellow Christians.

And he compared the Australian rugby player's actions to Destiny Church's Enough is Enough rally in 2004, when church members protested at Parliament against civil union legislation.