The monks were doing g Tum-mo, a yoga method that allowed them to achieve a profound state of concentration and greatly increase their body heat, some by as much as 17 degrees Fahrenheit in their fingers and toes.
Today, Buddhist monks across Tibet still practice g Tum-mo, raising their body temperature before prayers to feel the effects of their minds on their bodies.
Monks in the Himalayan region of Nepal also use this technique, but instead of focusing on their breathing, they think about the harm they can do with their hands during prayer times (because violence is not part of Buddhism).
Body heating exercises date back at least as far as 535 AD, when Indian monks developed a series of movements they called "aparigraha" (non-possessiveness) to help release anger and improve mental focus.
These exercises are still performed today by Hindu priests who aim to purify their mind and body before important rituals.
In America, Tibetan Buddhists use a similar exercise to calm their minds before meditation sessions. They call it "gong-tum."
Gong-tum means "heat meditation" in Tibetan language.
The monks sought to dry the body from the inside out, eliminating the self of fat, muscle, and fluids before being buried in a pine box to meditate during their final days on Earth, using a rigorous diet foraged from the neighboring mountains of Dewa, Japan. They would eat nothing but water and mountain plants for two years so that at the end of that time, their bodies were completely free of waste material.
There are several ways in which monks have preserved the bodies of saints for worship after their deaths. Some of them involve drying or otherwise removing all moisture from the body, such as by burying it whole with its head toward heaven and its feet toward the earth. This is done to make it possible to open the chest cavity and remove the heart, which is believed to be the source of spiritual power. The organs of the body are then donated to holy men who will burn them as an offering to God.
Other methods used by monks include stuffing the body with cotton until it can be buried in its own clothing, which was common in India. Still others freeze their bodies so they can be transported across long distances by camel or ship. There are even some monks who strip their corpses of flesh!
In conclusion, monks have been known to mummify themselves for preservation purposes.
They learn to regulate an energy force called as "chi" via meditation. To convert their bodies into armor, the monks employ Qi Gong and a unique way of breathing with the lower belly. This enables them to endure tremendous strikes, such as those delivered by harmful (and occasionally sharp) things. They can also withstand falls from great heights without injury.
Monks begin training when they are young, learning self-discipline, focus, and determination. They practice these skills daily in order to achieve maximum strength and stamina.
In addition to physical training, monks study different philosophies and theories on the nature of reality. This allows them to respond effectively to situations that might otherwise defeat a less knowledgeable person.
When you become a monk, you give up most forms of entertainment in order to have time to read books and discuss ideas. You also have limited contact with people, which gives you more time to practice meditative techniques. Eventually, you will be able to resist temptations that would normally cause a normal person to fail.
Although monks seem weak, they are actually very powerful. Their ability to withstand injury is due to their mind-body connection. When their body suffers, so does their mind. This makes them feel pain as much as or more than ordinary people, but it also gives them motivation to keep practicing.
What is the significance of certain Buddhist monks setting themselves on fire? In protest of the Vietnamese government's persecution of Buddhists, Buddhist monk Thich Quang Duc poured gasoline over his body and lit himself on fire in 1963, retaining his contemplative position as his body burnt. The photo taken by a news crew outside a hotel where he had parked his car showed Duc still sitting in his final position after half an hour, with people coming to see him off. This provoked great interest abroad, especially in Europe, where such things are not normally reported in the media.
This image has become a symbol for religious freedom in Vietnam, as well as protest against the Vietnam War. Since then, other Buddhist monks have done the same in further protests against the treatment of their faith.
There are several reasons why a Buddhist monk might set himself on fire. It can be as a protest against war, occupation or injustice. Or it can be as a demonstration of repentance or of devotion to God. Sometimes it can even be a practical joke.
Buddhist monks usually carry around small bags called "ubos" which contain items they might need during their meditation sessions (such as rice or salt). Sometimes they feel too distracted to meditate properly so they burn these items as a form of ritual cleansing.