The Gayatri Mantra is the most sacred mantra in Hinduism, and is to be said at least 12 times a day by all those born into the Brahman Caste. It is something like the Hindu Lord's Prayer; and there are two forms, the better known short form and the lesser known long form. Te only difference is in the formal preamble: The short form uses three and the long uses seven lokas or worlds or realms to address before moving to the mantra proper. I am going to expound on the long form, which begins in the following way:
Om Sat Yum,
And then the body of the mantra which I am not going to write, as it is not germane to this exposition.
Going from the top to the bottom, the sphere of influences gets larger and larger, so that the first realm or Bhur is the smallest and Sat Yum is the largest. This is important, that in one sense the form is upside down, and from the closest to the largest "worlds" or "realms". Here we go. Understand that Sanskrit is considered the Divine Language, and it's words each have many meanings simultaneously, and to translate into English (which is a surface language), is a daunting task:
Bhur is the realm of the Earth under us.
Bhuvaha is the realm of the Atmosphere
Svanaha is the realm of Space (but the word "Sva" means the "self" as in Svastika or the chakra Svanisthana)
Mahaya is the "Great" realm
Janaha is the realm of "Generating" or the realm of categories
Tapaha is the realm of Divine"Heat", or Ardor, or Work, or Effort, or Suffering, or Austerities.
Sat Yum simply means ISness, or TRUTHness or BEINGness.
So now we go in the other direction and make some comments:
Sat Yum is the Three in One of Gurdjieff's expositions of the three forces, which follows the Samkya; and the Trimurti, which are the three faces of God (Siva, Vishnu, Brahma), and his attributes which are Satchitananda. All compound words in sansrkit become ONE word, so Satchitananda is ONE but can be broken into three constituent parts.
Sat: Truth; Being; ISness; Suchness; Reality.
Chit: Awareness; Consciousness.
Ananda: Bliss; Unopposed Will; Unfettered Creative Force.
Now in the Three in One realm, there is the truth being and awareness of all that is. And as Mr. Gurdjieff tells us, this is unknowable, because our awareness cannot concieve of the third force or of the three forces as one seemless whole, but this is the exact same idea as the Holy Trinity of Chirtianity, which got it from the Sanatana Dharma, the permanent and neverchanging wisdom.
Just below the Singular Trinity there appears the realm of "heat". Ardor, Divine Love, Work and Suffering which exists at all levels of the Creation.
The Creator has two great laws or barriers that may not be breached, and they are the "objective speed of light" and "absolute zero degrees kelvin".
Scientists have gotten VERY close to absolute zero, something like .00000001 degrees above absolute zero, but to get that low takes more and more energy from outside to lower the temperature and more time to do it in because the less heat there is somewhere, the slower everything moves and takes. So that calculations have shown that to reach absolute zero would take more energy than exists in the entire universe, and it would take longer than the age of the known universe to do it in.
Now the word tapas, which has one of it's English translations as Heat, is so multivalent that a thousand words in english can convey it's meaning. There is no translation of Tapas into English.
But there is this fact, heat is ardor, and work, and suffering. It is the work and suffering that we are interested in. In the ascetic language of the Yogins and Fakirs (and taken up by the Buddha), all is suffering; all existence is "suffering". So all the austerities taken up by the fakirs (such as standing on one leg or pointing ones finger to the sky for TWELVE YEARS!) is a replica of the suffering of the Gods, like Shiva, who practices austerities for a thousand years or more in between visiting his wife or other duties or affairs.
I am not advocating keeping your arm up for 12 years, but some sit at desks making "money" for longer than that and they do not consider it a waste of their life-force. Who ends up with something permanent? Some business men think of these Yogins and Fakirs and think it is a "sickness" and a waste. I suggest that they might be those who "waste" what life they have. by seeking in THIS realm what is not here -- unending happiness and security.
But this Intentional Suffering of the Yogin or Fakir is designed to follow certain laws. One, to replicate the suffering of the Gods: in other words, to take a load off God by taking up some of his tapas and suffering. This is identical to the Christian vowing to make a gift of his or her suffering to the "Body of Christ"
Another aspect of this Intentional Suffering is to recieve what are called "Siddhis" or "perfections, where the Yogin is given powers and a measure of the authority reserved by the Creators regent, Great Nature.
What does Mr. Gurdjieff mean when he states that he has developed the power and force to "kill a Yak at a range of 10 miles"? Does anyone think this power and force comes for free?
No, Mr. Gurdjieff only developed such authority as he possesed by great suffering, intentional and with a knowledge of it's purpose.
Jesus is the exemplar of Intentional Suffering, and he underwent the Agony and Passion (both translations of tapas), with Intentionality and Purpose.
Later, the Desert Fathers followed the way of the Fakirs, like Simon the Stylite, who lived on top of a pole for years, of the other desrt fathers who wore wool cloaks, so that they would suffer an endless itching and disconforture, as a permanent reminding factor. The Arabic word for wool is "suf", so the term Sufi likely came from those Christians in North Africa who had learned from the Proto-Hindus, those of the Sanatana Dharma.
There is a rich tradition of suffering for Christ, without those who do so not realizing that they are folllowing a tradition of Intentional Suffering that goes back past the mists of recorded history.