The heavily tattooed convicted murderer towered over him and growled: "I am so angry with you".
Peter Mittermuller was a bit scared.
But the prison inmate was angry because Mittermuller hadn't entered his life sooner - that is, before he was serving a life sentence.
Mittermuller, a German native, left his job as an environmental engineer 14 years ago to devote his life to teaching breathing techniques - a skill he says changed his own life.
He has special treatment units at four prisons across the country where inmates learn breathing techniques, helping them let go of trauma, Mittermuller says.
"Somebody who's going into prison, it has to do with his childhood.
"Nobody is born and says: ‘I will become a criminal' - everybody is born with a smile. But on their way they're losing it.
"The breathing helps to erase those negative imprints."
One inmate, a "lifer", approached Mittermuller after a course and told him he was angry.
"I thought he'd had a good experience so I thought: ‘Oh my god, what is happening now?," Mittermuller recalls. "I was a bit afraid.
"But then he said: ‘If you had come 20 years ago I never would have landed here."
Many inmates end up inside partly because of a dependency on drugs or alcohol, Mittermuller says - vices he can relate to.
When he moved to New Zealand he worked in Auckland in project management, helping businesses become more sustainable by decreasing their waste outputs.
The job was full-on, and the increasing workload combined with the challenge of a new language meant Mittermuller developed a short temper.
"I thought I knew how to deal with stress. For me that was beer, my red wine and my cigarettes.
"Somehow it didn't really work as it used to."
His boss told him something had to change.
He looked into different groups, including anger management, but nothing really stuck.
Then a friend told him about a course in breathing techniques, but being a self-confessed stubborn engineer, Mittermuller wanted nothing to do with "that soft stuff" taught by a guy with a long beard and long hair.
"I said: ‘Are you crazy?'
"I had been breathing for 40 years at that time, what the heck?"
Eventually he did it and to his amazement, his life changed.
"I could do my work in a much quicker time and was not swinging backwards and forwards.
"That's what happens when you get stressed, the mind travels to the past and the future and back again.
"Suddenly I had this simple tool - breathing techniques, doing it every day for 20 minutes and it totally changed my mind."
The breathing techniques that Mittermuller learnt then, and teaches now, stem from the yogic science of breath taught by the Art of Living Foundation, a not for profit organisation founded in 1981 in Bangalore, India, by spiritual leader Sri Sri Ravi Shankar.
The organisation operates in 152 countries and the programmes are guided by Shankar's philosophy of peace: "Unless we have a stress-free mind and a violence-free society, we cannot achieve world peace."
The Art of Living offers programmes that include breathing techniques, meditation and yoga, recognising that the breath connects the body and mind and if harnessed, can be used to reduce accumulated stress, Mittermuller says.
"From childhood on we're starting to create information.
"Like your phone if you load more and more information one day it's full, and we don't have a tool to clean it.
"This is what the breathing technique does, it cleanses that memory chip."
The tools he teaches include how to regain lung volume, of which we typically use just 30 per cent. By regaining that volume, we have more energy and the breath helps to rein in the emotions - even by simply taking a deep breath in and out we are able to calm the mind.
Mittermuller's work with prison inmates started in 2006. A prosecutor did one of his courses and recognised the benefit it could have for people who took drugs in an attempt to settle their mind.
"My heart is with people on the edge," Mittermuller says.
"Back in German I was always looking for something to calm my mind because I felt so bombarded with all the thoughts coming in, sometimes you just want to shut it up."
A friend of his in New Zealand was imprisoned for drunk driving offences.
"I visited him a few times and I thought there's so much lost there. I thought, I need to do something."
He did a few trials and now, about eight years later, more than 2000 inmates across the country have done the course.
For Mittermuller, who was raised a Catholic, the decision to devote his life to teaching a form of spirituality derived from ancient India wasn't a light one.
His father is a strong Catholic and two of his cousins Catholic priests.
But Mittermuller says religions may have different gods, places of worship and languages, but the principles of spirituality are the same the world over.
"Religion and spirituality is like a banana - religion is the outside and spirituality the inside.
"The outside is the symbols and the inside is having the happiness, the contentment, being helpful, being inclusive, it's the same across everything."
Mittermuller's teaching has taken him to Samoa, Fiji, and post-earthquake Christchurch where he stayed for two years.
There was one woman who had slept in her sleeping bag in the doorway for three months since the February earthquake, afraid to go back to bed.
She started the course on a Thursday and by Saturday she was back in bed with her husband, Mittermuller says.
"We had an earthquake, she woke up, did the breathing, and went back to sleep.
"Her husband could not believe it so he came to the next one."
Sometimes Mittermuller's mind kicks in and reminds him of the financial security of his former job, and whether he wants to continue living out of a caravan in order to teach others.
"I am German, I used to be a civil servant so I had my career planned.
"But when your energy is low that's when doubts come in, so I just do the breathing and it goes."
Mittermuller has recently been in Bangalore for part of the training he's done over the last year to learn how to teach mantra meditation, where the participant is taught to use a simple sound mentally which allows the mind to settle down and let go of all tension.
His next meditation course is August 1 to 3, for more information contact Tessa on 021 057 4011 or email firstname.lastname@example.org.
- Taranaki Daily News
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