Om May no harm be done Here, May the vessels of the great Seers continue in Salvation,
May these movements be in accord with Divine Will, May this desire be motivated by Love,
May what is not beneficent wither to obscurity.
The English translation of the Brihadaranyaka Upanishad used here, is a copy of an original 1934 translation by Swami Madhavananda used in a 1950 edition of 'Brihadaranyaka Upanishad - Shankara Bhashya translated by Swami Madhavananda'. There are later editions of this book available at Amazon.com at the time of writing.
If studying this Upanishad or reading the following commentary it is essential to have a copy of this book with Shankara's commentary because it is needed as the master reference.
The Brihadaranyaka Upanishad is not just a scripture of a religion, It is a philosophy that naturally understands the scriptures (not necessarily religious practices or doctrines) behind all the great religions and would have no contentions with any of them.
The Philosophical discipline within the Brihadaranyaka Upanishad is a work that explains, in authentic logical terms, the fall into ignorance that was caused through that first desire leading to the forgetting of the existence of the one non-dual Absolute, Brahman, or God.
The knowledge revealed within this Upanishad (Sruti), it is said, came with Creation; meaning its knowledge remains as the one and only non-dual consciousness which also experiences "our" birth into the universe from the stillness of Absolute Knowledge and Consciousness. The agents for receiving and recording the Vedas were the Rishis of ancient times. In this work perhaps the Rishis would have been called Prophets in modern language.
Shankara in his commentary on this Upanishad said that it was "composed for the sake of those who wish to liberate themselves from the world, in order that they may acquire the knowledge that the Absolute Brahman and the individual are the same." "A knowledge by which the liberation from the cause of the world is accomplished".
Although the horse sacrifice ritual is the highest or greatest of all the rituals, the intention of this Upanishad is not to glorify the material world or to prescribe the performing of the horse sacrifice ritual itself or indeed any of the rites and rituals which it describes. This Upanishad will explain that all such rites and rituals came into being through mankind's needy desires caused by his feelings of incompleteness which were caused through his original forgetting and ignorance. Ignorance at all times means the ignorance or forgetting of the fact of mankind's identity with the one true non-dual existence of the Divine, God, Brahman or the Absolute, his true home. It follows, therefore, that the horse sacrifice ritual and all that it is desired to produce represents the sum of mans ignorance or the totality of his forgetting of the one true Divine existence.
The Brihadaranyaka Upanishad has the understanding that the cause of all desire is mankind seeking to complete itself after the forgetting that his true completeness already exists eternally with the Divine. The Brihadaranyaka Upanishad understands that rites and rituals are mans way of seeking to replace that forgotten "something" that is missing in this life experience. Therefore, the Brihadaranyaka Upanishad speaks through the highest of these rituals, the horse sacrifice ritual, to address those that are in ignorance of their divine unity.
Through describing what the needy and ignorant man desires from his rituals this Upanishad is in fact explaining all that mankind has forgotten about his true divine identity and natural eternal completeness. Through the remembrance of this truth his divine unity will once more become consciously known by him and through this conscious knowledge his way back to that Divine unity can be realised, this is the purpose of this Upanishad.
When the Upanishad appears to speak of glorious worldly results its subtle or secret meaning is to highlight the unreality of all material forms, which are only the inglorious result of achieving material objects of desires and moving deeper into materialism, which is the inglorious downside of an apparently glorious vital force which is itself merely the desire to experience material life, and the corresponding increased forgetting of the Divine Absolute.
In chapter one we will have described for us the universe as formed from the objects of the horse sacrifice ritual.
The true meaning of this symbology is that the universe has no existence in truth, its existence consists of name and form only.
It will be explained in subsequent chapters how the universe depends entirely on desire for its existence.
It is seen that the universe has a beginning, therefore it is not timeless, it is subject to entropy and decay. Because the universe has a beginning it will have an end.
It is the purpose of the Upanishads to reveal that the Absolute, God or Brahman is the one true existence, is beginning-less, unborn and without cause, is dependent on no other and alone exists timelessly.
Considering Adi Shankara's Bhashya, what is the need for further comment?
Shankara's Bhashya is a verse by verse commentary on the essence of the teaching from the Brihadaranyaka Upanishad.
But, Shankara at that time realised the need to explain, protect and promote the Upanishads and Advaita; This was a task requiring highly learned academic and logical disciplines to protect the Vedas from political opponents ( e.g. Mimamsa and Samkhya) and Buddhism in general. As such any subtle meaning of the Sruti that requires the intuition of an open heart to see and accept, which is a way of the Sruti, could not perhaps be entirely exposed.
The provision for objections on the grounds of logic and the subsequent thorough dispatching of those objections reduces the ease of accessibility to Shankar's commentary because it is primarily designed to answer academic criticism.
Our commentary is to the point and exposes much of the subtlety of the Sruti.  We have taken this path due to not being aware, in our experience, of its subtle knowledge arising in any conversation.
Subtleness needs time and association with the ways of the scriptures for that subtle meaning to be seen. We feel this directness of our commentary may be of use at this time due to our modern way of living offering many reasons why we should not spend too much time on esoteric spiritual contemplation. Dharma, society's laws and its morals offer us the assurance that through compliance with this way of life we will please God, and therefore we will find God. As righteous as such a way of life undoubtedly is, it seems God is not finally found through well meant action, merit or work alone. The Upanishads, in particular the higher philosophical understanding of the Brihadaranyaka Upanishad reveals that to obtain true liberation through the Divine, that Divine Truth has to be consciously realised, because all this takes place within consciousness.
The Upanishad teaching was originally an oral tradition and their format aided their correct transmission. The word Upanishad means "to sit down near", meaning to sit and listen to the sage passing on the teaching.
This Upanishad needs to be read and contemplated upon, in its entirety, many times, in order to become attuned to its layers of subtle meaning. By allowing ones ears to become accustomed to its archaic language and symbols greater clarity of understanding is achieved.
As far as we are aware there is no other complete verse by verse commentary on the Brihadaranyaka Upanishad. The Available commentaries tend to refer to sections or subjects in general. It seems to us that aspirants reading the Upanishad for themselves might like to compare directly their understanding of any particular verse with another Advaitin.
It is our conviction that this Sruti reveals the highest wisdom that authoritively explains the reality behind all events for all time and that this would not be disputed by those of higher understanding.
Further to the above it is also our understanding that the philosophy of this Upanishad reveals that Existence is a singularity, meaning that The Absolute or God or Brahman alone exists. Our commentary is based on this understanding to reflect that light of Advaita or Non-Duality.
Due to its revelation of higher knowledge, the study of this Upanishad should not be undertaken alone. Gaining higher truth causes a phase of discomfort due to the necessary questioning of our former comfortable worldly identity, this is natural and to be expected. If quite profound discomfort is experienced then please stop reading this commentary and seek a teacher or the company of like minded students, really nothing will be lost. One can read instead The Crest Jewel of Wisdom by Adi Shankara which describes the same truth. The difference is there Adi Shankara describes the beauty of the Truth, here this Upanishad reveals the delusions that maintain the forgetting of our Divine identity. But, that said, eventually all are destined to experience the sure knowing that all will be well because, despite all words or feelings to the contrary, one just cannot, in reality, be lost within Divine unity.
The word ignorance in all cases of its use means the forgetting of one's true identity with the Absolute or God or Brahman, the only real ignorance.
Chapter one deals with the forms of ignorance from the Creation of the universe through a vital force of desire (Hiranyagarbha), to becoming the first born and the error of his gods of duality and the class and cast systems.
Guadapada, in his famous commentary on the Mandukya Upanishad suggests that it is the nature of the absolute to make the creation cycle of the Universe manifest. But, whichever cause one accepts, this Upanishad explains that it is the ongoing desire for worldly experience that maintains the appearance of creation.
Chapter two continues from chapter one by explaining how man's continuing desire for worldly knowledge due to his forgetting of his non dual identity with the Absolute, becomes an imagined divine vital force. From this vital force of desire man sees a Brahman or god with material attributes and proceeds to project further gods to oversee his desires.
Concerning the "Vital Force" it seems to us that the term could cause false impressions that last overly long.
Swami Vivekananda, in his Complete Works of Swami Vivekananda, Lectures and Discourses, cosmology volume 2 has said :-
"Prana you can call in English life, the vital force; but you must not restrict it to the life of man; at the same time you must not identify it with Spirit, Atman."
Taking from Swami Vivekananda's statement support for the understanding that the vital force is not The Absolute, God or Brahman then in proper terms of Advaita we do not see this vital force, as being anything other than that due to Maya.
Reference also Gaudapada Karika Chapter 2 Verse 19. "Atman is imagined to be Prana (life)...This is the Maya of...Atman, by which he himself has been deluded".
Therefore, we conclude, No vital force exists materially or spiritually on its own. There is no vital force of divine desire.
Due to the ignorance arising from forgetting the reality of The Non-Dual Absolute, that it is free from all desire, the ignorant assume that a divine vital force exists and it is the desire of the Divine that they work, create and materially flourish in "their" life.  Therefore, a vital force represents material desire for the worldly, which causes and maintains material creation. The Sruti describing the effects of a vital force describes the desire of the person that has forgotten his or her identity with the Absolute, God, or Brahman. Therefore, there are philosophical considerations. The Sruti is infinitely wise in purpose and gentle in Execution.
Chapter 3 starts with the story of Yajnavalkya taking a prize, which was offered by the Emperor Janaka of a thousand cows each with its horns covered in gold. The ultimate purpose of this story is to prove that Yajnavalkya, the sage of this Upanishad, is the most erudite and learned of all the wise scholars present. During the debate the scholar Gargi shows herself to be a great sage in her own right and is Yajnavalkya's wisest interrogator. Having eventually proven himself (to us also, is an intention) to be the greatest teacher, Yajnavalkya will then proceed to teach all of us, including the wise Emperor Janaka, the truth of the non-dual Absolute.
Chapter 4 is the last chapter that comprises the Upanishad proper. This chapter has Yajnavalkya continuing in his role as a teacher to complete the teaching of the Upanishad with Emperor Janaka as his student. The famous conversation between Yajnavalkya and his wife Maitreyi is once again repeated during which the highest truth of the non-dual Absolute consciousness is revealed.
Chapter 5 & 6 differ to the content of the main Upanishad in that these last two chapters are more of a supplement or appendix, they are a collection of various ritualistic verses only.
The aim of the Brihadaranyaka Upanishad is to lead one to Moksha, liberation from the ties of this world. The result of the karma or actions described in chapters 5 & 6 would lead to further material experience within the world only, but we do not mean to say they are not without benefit.
The scriptures understand that the young householders, the husband and wife are filled with natural desires. The young householder, following his desires also has a need for possessions and the need to protect those possessions.
Therefore, although we have focussed on the higher philosophy of the Brihadaranyaka Upanishad in our commentary it is not our intention to actually dismiss any of the supporting scriptural teaching. This commentary is simply our way of discussing Divine reality.
The Seer of this Upanishad, as said, uses the symbology of the ancient Ashvamedha (horse sacrifice) ritual to reveal the results of ignorance and desire. The Ashvamedha was a royal ritual and its purpose was for prestige, power and gain. First the horse was consecrated according to the procedure prescribed in the Brahmanas under the auspices of a Priest. Then the sanctified horse was allowed to roam free but watched for up to a year. All that the horse covered in that year, or one sun cycle, which symbolised the world, the King would be right to claim as the fruits of his desires. The horse would then be ritually sacrificed through which the king gained his desire for the world (rebirth into the universe).
This Upanishad is indeed a Forest of wisdom. There are two paths through this forest each attaining different goals, re-birth into the material world or liberation from the world. The conscious experiencing of each path is described without judgement.
One path is not predictable, will take its own course, and depends entirely on the light of Divine Knowledge being seen and accepted as the true guide.
The other path is well trodden and guided by Dharma and the material desires of mankind. It is not assumed which path the seeker truly desires.
The forest is complicated and the paths meander without clear pattern often crossing without warning. At these crossroads there are signposts but these can be understood only if you know the goal of your true desires, the signposts do not presume to say right way or wrong way.
If you enter this forest without a guide hoping you will recognise what it is you need when you see it you would likely continue travelling in circles for some time.
Ohm peace, peace, peace.