Atma Bodha – Chapter9

ब्रह्म स्वरूपम् Nature of Brahman Verse 54-62
Verse 54
On attainment of Brahman, one becomes complete and accomplished
यल्लाभान्नापरो लाभो यत्सुखान्नापरं सुखम् ।
यज्ज्ञानान्नापरं ज्ञानं तद्ब्रह्मेत्यवधारयेत् ॥ ५४॥
यत् लाभात् न अपरः लाभः यत् सुखात् न अपरम् सुखम् यत् ज्ञानात् न अपरम् ज्ञानम् तत् ब्रह्म इति अवधारयेत्
यत् लाभात्- from the attainment of which न- not अपरः-other लाभः-attainment यत् सुखात्-from the blessedness of which न-not अपरम्-other सुखम्-blessedness यत् ज्ञानात् –from the knowledge of which न -not अपरम्- other ज्ञानम्-knowledge तत् ब्रह्म-that to be Brahman इति-thus अवधारयेत् –to be realized
In previous shloka Acharya mentioned that a person who has become free from upadhis merges with Brahman like a pot space mergesm into total space. In the shlokas 54, 55, 56 and 57 he explains the nature of Brahman (ब्रह्म स्वरूपम्), and reward of obtaining knowledge (ज्ञान फलम्).

Verses 54 to 58 end with the phrase तत् ब्रह्म इति अवधारयेत्. Understand that to be Brahman. Behold that to be nature of Brahman

Realize that to be Brahman, the attainment of which leaves nothing more to be attained, the blessedness of which leaves no other blessing to be desired, and the knowledge of which leaves nothing more to be known.

यत् लाभात् न अपरः लाभः – Apart from this attainment there is none other. This attainment is complete. Nothing is missing. Suppose a jnyani tries to build an Ashram, he does so, with satisfaction but not to gain satisfaction. The word अपर means different or greater than. There is no greater benefit than obtaining the attainment of self-knowledge, it also means there is no other accomplishment than self-knowledge.
यत् सुखात् न अपरम् सुखम् – apart from this blessedness there is none other. After getting the Brahmanada, there is no other ananda greater than this.
यत् ज्ञानात् न अपरम् ज्ञानम् – apart from this knowledge there is none other. This knowledge is total and nothing else to be added. He gets physical, emotional and intellectual satisfaction. All other knowledge is ramification of avidya.
तत् ब्रह्म इति अवधारयेत् – realize that to be Brahman. By attaining Brahman, all these satisfactions will be obtained by Jivanmukta.
Attainment of Brahman (ब्रह्म प्राप्ति) is not like getting a progeny (पुत्र प्राप्ति), getting wealth (वित्त प्राप्ति,) or constructing a house (गृह प्राप्ति). This material attainment is fleeting in nature and the cause of more and more desire. A man who had no house has built a house. He has satisfaction only for some time and later he looks into what are missing in the house. Brahma prapti is not of this category. He feels complete and nothing remains to be added. He has everything. All other happiness is insignificant.
Paramarthanada: Jnyana phalam of gaining self-knowledge are:
1. Attainment of self-knowledge
2. Removal of ignorance and related misconceptions
3. Freedom from ahankara and mamakara
4. Jivan mukti or videha mukti.
Realization of self is the greatest gain, the greatest knowledge, greatest asset, having gained which there will be never any sense of incompleteness. Something new is sought only when there is imperfection or incompleteness. Then one tries to gain more. With the dawn of self-knowledge, one is complete without any imperfection. A jiva fails to know that he is the self but out of ignorance; he thinks he is limited body, mind and intellect complex.
Verse 55
When Brahman is realized nothing else remains
to be understood. That is the end of journey of samsara,
यद्दृष्ट्वा नापरं दृश्यं यद्भूत्वा न पुनर्भवः ।
यज्ज्ञात्वा नापरं ज्ञेयं तद्ब्रह्मेत्यवधारयेत् ॥ ५५॥
यत् द्ष्ट्वा न अपरम् दृश्यम् यत् भूत्वा न पुनर्भवः यत् ज्ञात्वा न परम् ज्ञेयम् तत् ब्रह्म इति अवधारयेत्
यत् द्ष्ट्वा-which when seen, perceived न-not अपरम्-anything else दृश्यम्-to be seen यत् भूत्वा-which having come into being न-not पुनर्भवः-to be born again in the world यत् ज्ञात्वा-which when known न-not ज्ञेयम्-to be known तत्-that परम्-supreme ब्रह्म-that to be Braham इति-thus अवधारयेत्-to be realized

Realize that to be Brahman which when seen nothing more remains to be seen, having become which, one is not born again into this world of becoming, and which when known, leaves nothing else to be known.
यत् द्ष्ट्वा न अपरम् दृश्यम् – Having seen which nothing more remains to be seen. The word seen here means ‘realized’. Having realized that the basis of all ornaments is gold, the basis of all waves is water and the basis of all mud pots is the clay, the basis of all names and forms of the world is Brahman.
यत् भूत्वा न पुनर्भवः- having become which one is not born again in this world. If you have become Brahman, there is no need for you to become anything more. Really speaking Brahman is not becoming; it is our own nature. भावः means to become. An incomplete man wants to become or get so many things. Paramarthananda: First, he is not satisfied with his bachelor “I” and wants to change into a husband “I”. After that the married “I” wants to become a father “I”. Then he wants to become a house owner, car owner, international traveler “I”. Still, he is not satisfied. He wants to be father-in-law “I”. There is no end to this भावः or becoming. Krishna calls such people as अक्रुतात्मानः or unrefined, unpurified in Gita. Here is the Shloka:
यतन्तो योगिनश्चैनं पश्यन्त्यात्मन्यवस्थितम् ।
यतन्तोऽप्यकृतात्मानो नैनं पश्यन्त्यचेतसः ॥१५:११॥

The yogis, striving for liberation, behold the self biding in themselves but those who are unpurified and undisciplined are unable to perceive him in spite of their struggle.

क्रुतात्मानः therefore is one who has converted the relative “I” into Brahman “I”. With this the journey of भावः ceases. I become the absolute Brahman.

ज्ञानेन यत् भूत्वा न पुनर्भवः this happens not by any event but by knowledge of transcendental spirit.
यत् ज्ञात्वा न परम् ज्ञेयम् – and having known which nothing remains to be known. A man who has realized Brahman is a complete man. If you do not have all knowledge you crave for more.
तत् ब्रह्म इति अवधारयेत् – realize That to be Brahman. Bhagavat Gita calls this as ब्राम्हीस्तितिः:
एषा ब्राम्हीस्तितिः पार्थ नैनां प्राप्य विमुह्यति । स्थित्वास्यामन्तकालेऽपि ब्रह्मनिर्वाणमृच्छति ||२:७२||

O Arjuna, this is the superconscious state of the mind (established in Brahman). Attaining this state one overcomes delusion. And established in this state even at the end of life, he attains the final, irrevocable state of God-communion.

Verse 56
Realize that to be Brahman which pervades all quarters and is
the nature of existence- consciousness-bliss and eternal

तिर्यगूर्ध्वमधः पूर्णं सच्चिदानन्दमद्वयम् ।
अनन्तं नित्यमेकं यत्तद्ब्रह्मेत्यवधारयेत् ॥ ५६॥
तिर्यक् ऊर्ध्वम् अधः पूर्णम् सच्चिदानन्दम् अद्वयम् अनन्तम् नित्यम् एकम् यत् तत् ब्रह्म इति इति अवधारयेत्
तिर्यक्-all the sides ऊर्ध्वम्-above अधः-below पूर्णम्- fills up सच्चिदानन्दम्-which is existence-knowledge-bliss अद्वयम्-non-dual अनन्तम्-infinite नित्यम्-eternal एकम्-one यत्-which तद्ब्रह्म-that to be Brahman इति-thus अवधारयेत्-should be realized

Realize that to be Brahman which pervades all quarters, above and below, which is existence-consciousness-bliss absolute, non-dual, which is infinite, eternal, and the one and only one.

तिर्यक् ऊर्ध्वम् अधः पूर्णम् – That which pervades everywhere, all the sides, above and below; that which is full at all levels. At all level Brahman is पूर्णः he fills up everything, he is complete.
सच्चिदानन्दम् अद्वयम् –which is of the nature of existence-awareness-bliss, non-dual. It cannot be all- pervading unless it is non-dual. अद्वयम् means free from all types of differences सजातीय, विजातीय स्वगत भेद रहितम्. There is no sentient or inert entity other than Brahman. A limited thing alone can have parts and boundaries. Brahman is unlimited, eternal, infinite, and one homogenous entity without boundaries and limitations (अनन्तम् नित्यम् एकम्). Paramarthananda says- at the level of Brahman, purnatva is called अनन्तम्. When we discover that purnatva in our mind it is called आनन्दः (ananda).
अनन्तम् नित्यम् एकम् – infinite, eternal, the only one. अनन्तम् अंत रहितम् without an end. अनन्तम् indicates देशतः अपरिछिन्नम्- there is no limitation by space meaning infinite.
नित्यम् indicates कालतः अपरिछिन्नम् – there is no limitation by time meaning eternal. एकम्- one alone. एकम् indicates वस्तुतः अपरिछिन्नम् there is no limitation by object.
यत् तद्ब्रह्म इति अवधारयेत् – Realize yourself to be that Brahman. The fourth line is similar in all shlokas from 54 to 57. All spiritual speakers have to realize one’s true identity as Supreme Being. The self which is परिछेद शून्यम् यत् अस्ति तत् ब्रह्मन्.

Verse 57
Brahman is reached by a process of negation of what
it is not and assertion of what it is. It is a seamless bliss.

अतद्व्यावृत्तिरूपेण वेदान्तैर्लक्ष्यतेऽद्वयम् ।
अखण्डानन्दमेकं यत्ततद्ब्रह्मेत्यवधारयेत् ॥ ५७॥
अतद् व्यावृत्तिरूपेण वेदान्तैः लक्ष्यते अद्वयम् अखण्डानन्दम् एकम् यत् तत् ब्रह्म इति अवधारयेत्
अतद् -not this व्यावृत्तिरूपेण (व्यावृत्ति -seperation,exclusion, distinction रूपेण-appearence) –the process of negation, exclusion वेदान्तैः- by Vedanta philosophy लक्ष्यते-is indicated अद्वयम्-non-dual अखण्डानन्दम् (अखण्ड आनन्दम्)-indivisible and blissful एकम्-one यत्-which तत् ब्रह्म-that to be Brahman इति-thus अवधारयेत्-to be understood

Realize that to be Brahman which is seamless bliss, and the only one. The Upanishads indicate that this Brahman is reached by a process of negation of what it is not and of assertion of what it is.
अतद् व्यावृत्तिरूपेण –by the process of negating what it is not. अतद् means not that व्यावृत्ति रूपेण-by the process of exclusion. This process is called नेति नेति, “Not this, not this”. By this process all दृश्य वस्तु or perceivable objects – our body, mind, thoughts, ideas, theories and the whole world is negated as unreal or mithya and changing with time. So, they cannot be Brahman. Paramarthananda: Because everything we know are अनित्यम्, परिछिन्नम् and द्वैतम्. Vedanta negates all perceivable objects and, in the process, it also gets negated because it is also a Vishaya. प्रमेय is gone प्रमाणम् is gone and what remains is only प्रमाता. This will bring us to experience the blissful aspect of the Self. Ultimately what remains is true “I” or the self who is changeless, and witness of all changes.
वेदान्तैः लक्ष्यते अद्वयम्- indicated in Vedanta as the indestructible substratum. Only Self is indestructible and all others have shelf life, they have a date of birth and death.
अखण्डानन्दम् एकम् यत् – which is indivisible, blissful, and single entity. Paramarthananda: This pure happiness is not a part, product or property of the mind. It continues to exist even after the resolution of mind. अखण्ड means without a break, undivided, seamless. Purna is complete, it is not a प्रतिबिंब आनंद obtained in Anandamaya Kosha. It is original ananda atma. There is no pause for the bliss. It is available all the time 24/7. आनन्दम् is bliss. तत् ब्रह्म इति अवधारयेत् –Understand yourself to be that (तत्) Brahman.

Verse 58
Deities like Brahmaa enjoy only a part of the soul-bliss
prorata according to their heirachy
अखण्डानन्दरूपस्य तस्यानन्दलवाश्रिताः ।
ब्रह्माद्यास्तारतम्येन भवन्त्यानन्दिनोऽखिलाः ॥ ५८॥
अखण्डानन्दरूपस्य तस्य आनन्दलवाश्रिताः ब्रह्मा आद्याः तारतम्येन भवंति आनन्दिनः अखिलाः
अखण्डानन्दरूपस्य (अखण्ड आनन्द रूपस्य) –one whose nature is unbroken bliss तस्य-his आनन्दलवाश्रिताः (आनन्द लव आश्रिताः) –depending upon only a particle of this bliss ब्रह्माद्याः (ब्रह्मा
आद्याः) –the creator and the other deities तारतम्येन-proportionately भवन्ति –become आनंदिनः-blissful अखिलाः- all

Deities like Brahma and others taste only a fragment of the unlimited Bliss of Brahman and enjoy in prorata, their share of that bliss.

अखण्डानन्दरूपस्य (अखण्ड आनन्द रूपस्य) –The Lord’s nature of unbroken bliss. Lords’ bliss is his nature. The bliss is not dependent on any object. It is eternal and not subject to fluctuations. It is same all time. It is a symbol of fullness or purnatvam. There is no desire to get more because everything is available.
तस्य आनन्दलवाश्रिताः(तस्य आनन्द लव आश्रिताः)- लव-means section or cut, depending upon just a small portion of that total bliss.The maximum bliss of Brahman is not shared by anyone else. Others get according to their grade of heirachy and sadhana only a portion of the God’s bliss.
ब्रह्मा आद्याः तारतम्येन भवंति आनन्दिनः अखिलाः –the creator and other deities proportionately enjoy the bliss of their share. Who shares the Lord’s bliss? It is Brahma and other deities. Brahma is the creator Indra is the lord of heaven. Varuna is the Lord of rain. Kubera is the Lord of treasury. These deities share a part of the bliss according to their sadhanas. What about the happiness experienced by ordinary people? They do not share the original eternal bliss of God. Ordinary mortals get the reflected happiness which is a property of the mind and is called विषयानंद objective happiness or कोषानंद. It varies in quality and quantity from time to time, depending on the state of reflecting medium or mind. So, this called प्रतिबिंबानंद. The reflected happiness is subject to arrival and departure, degree and gradation depending upon the state of the mind. Happiness in Vedanta is defined as the feeling of पूर्णत्वम् or the degree to which a person feels full and non-lacking. The more a person lacks some thing or the other in life, the less happiness he will feel. When I realize that I, as Brahman, do not lack anything, then the mind is most tranquil, the Original Ananda shines brightest in the mind. Vishayananda is a portion of Brahmadanda. –Swami Chidatmananda.
Swami Chinmayananda says, “A relative picture has been drawn here to give us a wild quantitative measure of the infinite (bliss) in terms of a finite yardstick.”
The Taittiriya Upanishad has an entire Anuvaka (chapter) on “Relative Joy” enjoyed by the devatas down to the human being. Suppose there is a noble young man versed in Vedas, the best among rulers, strong in body and firm in mind and has the ownership of the whole world, that is only one measure of human bliss.
This human bliss, multiplied one hundred times, is one measure of the bliss of the human gandharvas, as also of a man versed in the Vedas and free from desires. Like this the Upanishad gives 11 grades of Ananda. The 11th grade is equivalent to just one unit of Brahmadanda. This comparison is only for our purpose of understanding since God’s bliss is infinite and beyond any measure.
Verse 59
The whole creation is permeated by Brahman like butter in milk. It is because he is spread everywhere, all actions take place in universe

तद्युक्तमखिलं वस्तु व्यवहारस्तदन्वितः ।
तस्मात्सर्वगतं ब्रह्म क्षीरे सर्पिरिवाखिले ॥ ५९॥

तद्युक्तम् अखिलम् वस्तु व्यवहारः तदन्वितः तस्मात् सर्वगतम् ब्रह्म क्षीरे सर्पिः इव अखिले
तद्युक्तम्-pervaded by that (Brahman) अखिलम्-all वस्तु-objects व्यवहारः-actions तदन्वितः (तद् अन्वितः)-are possible depending on that तस्मात्-therefore सर्वगतम्-permeating everywhere ब्रह्म-Brahman क्षीरे-in the milk सर्पिः – clarified butter or ghee इव-like अखिले-everything

The whole creation is pervaded by Brahman. It is because of Brahman that all actions are taking place in this universe. Brahman permeates everything as clarified butter permeates milk.

तद्युक्तम् अखिलम् वस्तु – All objects are pervaded by that ‘Brahman’. All the objects of the world have names and forms. So, we say that ‘is’ or that ‘exists’. ‘Is’ or ‘exists’ is nothing but सत् or existence or Brahman. When I say ‘I am’, that is also सत् or existence or Brahman. Brahman is consciousness. Everything that exists is consciousness.
व्यवहारः तदन्वितः – All actions are possible because of the pervading nature of Brahman. All actions mean
श्रुन्वन्, पश्यन् जिघ्रन् निमिशन् उन्मिशन्
प्रलपन्विसृजन्गृह्ण्न्नुन्मिषन्निमिषन्नपि |
Hearing, seeing smelling, eating, blinking and transactions done by the living beings. These actions are possible because Brahman exists in them as consciousness.
तस्मात् सर्वगतम् ब्रह्म – Therefore, Brahman alone permeates everything,
क्षीरे सर्पिः इव अखिले – even as butter permeates milk. Here the simile of butter and milk is given because butter in the milk is not visible directly. To get butter one has to churn milk. Similarly, to realize Brahman one has to do many sadhanas like Shraavana, manana, nidhidyasana, shama, dama, uparama and titiksha. The churning of the mind happens in nidhidyasana.
Just because we are not able to see god; it does not mean he does not exist. Just because we are not able to see butter in milk, it does not mean that butter does not exist in milk. The simile for ‘seeing’ God in all is ‘seeing’ butter in every drop of the milk.
Amrita Bindu Upanishad gives the same example in shloka 20. Here it is.
घ्रुतमिव पयसि निगूढं भूते भूते च वसति विज्ञानम्‌
सततं मन्थयितव्यं मनसा मन्थानभूतेन ॥ २०॥

Like butter concealed in milk, consciousness dwells in every being. It should be constantly churned with the churning rod of the mind.

Shwetaashwatara Upanishad 1:15 says:
तिलेषु तैलं दधिनीव सर्पिरापः स्रोतःस्वरणीषु चाग्निः ।
एवमात्माऽत्मनि गृह्यतेऽसौ सत्येनैनं तपसायोऽनुपश्यति ॥ १५
As oil in sesame seeds, as butter in curds, as water in underground springs, as fire in wood, even so this Self is perceived in the self. He who, by means of truthfulness, self-control and concentration, looks again and again for this Self, which is all-pervading like butter contained in milk, and which is rooted in self-knowledge and meditation – he becomes that Supreme Brahman, the destroyer of ignorance.

Verse 60
Brahman is free from all attributes
अनण्वस्थूलमह्रस्वमदीर्घमजमव्ययम् ।
अरूपगुणवर्णाख्यं तद्ब्रह्मेत्यवधारयेत् ॥ ६०॥
अनणु अस्थूलम् अह्रस्वम् अदीर्घम् अजम् अव्ययम् अरूपगुणवर्णाख्यं तत् ब्रह्म इति अवधारयेत्
अनणु-neither subtle अस्थूलम्-nor gross अह्रस्वम्-neither short अदीर्घम्-nor long अजम्-without birth अव्ययम्-without change अरूपगुणवर्णाख्यं (अरूप-without form गुण-quality वर्ण -colour आख्यम्-known as)-without form, quality, colour and name तत्-that ब्रह्म-Brahman इति-thus अवधारयेत्-to be understood

Brahman is neither subtle nor gross, neither short nor long. It has no birth, no changes, no form, no quality, no colour, and even no particular name.
In this verse Shankara is explaining in detail the meaning of the words सर्वगतम् ब्रह्म क्षीरे सर्पिः इव referred to verse 59. Brahman is the substratum of everything. It is an account of his existence; all that we perceive and do not perceive exist. The essence of this shloka is Brahman is free from all attributes.

अनणु अस्थूलम् अह्रस्वम् अदीर्घम् –
अणु means fine, minute, atomic. अनणु means course, large. Brahman is neither a small thing nor a big thing. स्थूलम् is gross big. अस्थूलम् says Brahman is not large. ह्रस्वम् is short, small. So अह्रस्वम् is not short or small. दीर्घम् is long, chronic. अदीर्घम् is therefore not long.
श्वेताश्वतरोपनिषत् ३-२० says:
अणोरणीयान् महतो महीया-
नात्मा गुहायां निहितोऽस्य जन्तोः .
तमक्रतुः पश्यति वीतशोको
धातुः प्रसादान्महिमानमीशम् ..3:20
The Self, smaller than the small, greater than the great,is hidden in the hearts of creatures.The wise, by the grace of the Creator,behold the Lord, majestic and desireless, and become free from grief.

अणोरणीयान् महतो महीयान् –Brahman is smaller than the smallest and bigger than the biggest.
अजम् अव्ययम् अरूपगुणवर्णाख्यं (अरूप गुण वर्ण आख्यम्) –
अजम्-one who has no birth. So, by implication he has no death also. He is infinite. अव्ययम् –no modification or change. The gross body has six types of changes namely, अस्ति जायते वर्धते विपरिणमते, अपक्षीयते, विनष्यति. Brahman has no change. He is always the same. अरूपगुणवर्णाख्यं (अरूप गुण वर्ण आख्यम्) – free from form, attributes, colour and names. Rupa is form or shape. He has no boundary. Guna means attributes such as good and bad qualities. Guna also means sattva, rajas and tamas. Brahman is beyond all gunas. Brahman has no Guna (निर्गुणः).
Brahman has no Guna or quality; neither good one nor bad one. Paramarthananda says: Vishishta dvaitins hold that Brahman is only free from bad traits. Advaitins say it is not right because even good attributes make Brahman relative. Brahman is अन्यत्र धर्मात् अन्यत्र अधर्मात् it is beyond dharma and beyond adharma. When we say Brahman is अगुणम् what is meant is that he is free from सगुण as well as दुर्गुण. अवर्णम् means does not belong to Brahmin or other Varna. आख्यम् means name. The names we use like Brahman, adhishtanam are mithya or not real. But Brahman or adhishtanam are not mithya. The name is mithya. Then what is satyam?
The epithets like gross, subtle, short, long, the gunas and the four varnas are the properties of the matter but not Atman. He has no name (आख्यम्) because he permeates everything. The limitless Brahman which is devoid of qualities is described here. Then how to describe Brahman? Dakshina Murti stotra says this nicely. The teacher expresses himself in silence. Here is the verse.
मौनव्याख्या प्रकटित परब्रह्मतत्त्वं युवानंवर्षिष्ठांते वसद् ऋषिगणौः आवृतं ब्रह्मनिष्ठैः ।आचार्येन्द्रं करकलित चिन्मुद्रमानन्दरूपंस्वात्मारामं मुदितवदनं दक्षिणामूर्तिमीडे ॥१॥

I worship Dakshinamurty, the young Guru, who teaches the knowledge of Brahman through silence, and who is
surrounded by scholarly disciples who are themselves established in Brahman. I worship Dakshinamurty who is the teacher of teachers, who exhibits chin mudra (sign of knowledge), whose nature is bliss and who ever revel in his own self.
This verse explains the essential nature of Brahman by silent exposition into which Jivanmukta merges.
तत् ब्रह्म इति अवधारयेत् – realize That to be Brahman.
Gross, subtle, shapes, sizes, names and all such qualities can exist only for an object which has boundaries and so becomes limited by space, time and object (देश काल वस्तु परिछिन्नम् ). But Brahman is that which is the substratum of everything i.e., everything is supported by Brahman, and everything is permeated by Brahman. Hence it can never be classified as gross or subtle or by any name. It is never the object of perception of any feelings or thoughts but verily the perceiver. It is THAT which exists and hence all that exits.
Verse 61
The luminating orbs get their luster from Brahman.
But they cannot illuminate Brahman.

यद्भासा भास्यतेऽर्कादि भास्यैर्यत्तु न भास्यते ।
येन सर्वमिदं भाति तद्ब्रह्मेत्यवधारयेत् ॥ ६१॥
यत् भासा भास्यते अर्क आदि भास्यैः यः तु न भास्यते येन सर्वम् इदम् भाति तत् ब्रह्म इति अवधारयेत्
यत् भासा- by the light of which by the luster of which भास्यते-are illuminated अर्क– the sun आदि-etc. meaning the celestials like the sun, moon, stars etc. भास्यैः-by the luminous orbs यः-that तु- -indeed न-not भास्यते-is illuminated येन-by which सर्वम्-all इदम्-this भाति-shines तत् -that- ब्रह्म-Brahman इति-thus अवधारयेत्- to be understood.
Realize that to be Brahman by the light of which luminous orbs like the sun and the moon are illuminated, but being themselves incapable of illuminating Brahman.

We are now entering the concluding phase of the text. The nature of the Self is so completely different from anything that we experience in this physical world, that we can hardly reach it through words. Yet that is what we are attempting through various analogies and similes.
The following commentary is based on Sathya blog and lecture of Swami Dayananda.
यत् भासा भास्यते अर्क आदि– By the light of which the sun and other orbs shine. It is the source light.
अर्क आदि means sun etc. This refers to shining orbs like the sun, moon, stars, lightning, and fire (सूर्य चंद्र नक्षत्र विद्युत् अग्निः आदि). We should be careful here. When we say because of the source light everything shines, we should not mistake that Brahman has a peculiar light. What this shloka conveys is that because of which awareness everything is known. Light means awareness. Shines means known. It is because of this awareness that the sun, moon, stars, lightning, and fire (सूर्य चंद्र नक्षत्र विद्युत् अग्निः आदि) become aware to us.
The word light or Jyoti (ज्योति) has a technical meaning in Vedanta. Light or consciousness is that principle in whose presence all the objects, emotion and thought become perceptible or known. In the absence of light things cannot be known.
The sun is the source of all light in the world. The moon reflects the light of the sun in the night. But their luminosity however is only at the physical level. भासा means luster. भास्य means to be made visible, to be brought to light. भास्यते is the verb meaning illuminates.
By this principle, the Sun, Moon, fire, lightening are all lights. Now, Vedanta goes further to say that the mind and sense organs are also lights, which “illumine” various aspects of the creation. The mind illumines the thoughts, emotions, feelings and ideas. In the presence of the mind alone things are recognized. If a person is absent minded many a thing escapes his attention. The sense organs which are also the “light” illumine form, colour, taste, texture, smell, sounds etc. Words are also treated as lights, as they can illumine or point out to objects. All the books, Scriptures are also a form of light, which illumines different aspects of the world and nature of Brahman.
भास्यैः यः तु न भास्यते– but which is not illumined by these भास्यैः(means the illuminating objects सूर्य चंद्र नक्षत्र विद्युत् अग्निः आदि)) luminous orbs. भास्यम् the illuminator or Atman. So, by these illuminated objects atman is not illuminated. That means Atman is never an objects it is ever the subject.
The second line switches over to the philosophical meaning of “luminous” or” illuminate”. What this means? It means to become ‘aware of’, or ‘to know’. भाति means shines, perception, knowledge. The light of the sun and moon does not illumine the self. On the contrary, the light of the self illuminates these two bodies to make them luminous.
येन सर्वम् इदम् भाति – by the presence of which all this shines, by the presence of which all this become visible. येन means by the presence of which refers to ब्रह्म प्रकाशेन (by the light of Brahman) ब्रह्म चैतन्येन (by the consciousness of Brahman). By the presence of consciousness, we become aware of all these. What do we know by consciousness?
1. Consciousness enables us to recognize all the world of objects, emotion and thought. So, it is called Jyoti or light. Consciousness is knowledge प्रज्ञानम् ब्रह्म.
2. Consciousness makes us aware of existence of things. But for consciousness we would not have been aware of existence of objects, emotion and thought. An object becomes known to us only if I shed my light of consciousness on it through my mind. Consciousness is सत्
3. Consciousness flows through the mind, but the ignorant mind does not know it. Consciousness illumines the intellect, the intellect illumines the mind, and the mind illumines the eye, which then illumines the sun. If consciousness is removed, we will not see the sun also
तत् ब्रह्म इति अवधारयेत् – That which illumines all other things but which has nothing else to illumine it – realize that as Brahman. It says the ultimate illuminator is “I” the Atma or Brahman, the Consciousness, the atma-chaitanya. The light of Consciousness illumines the mind, which in turn illumines the sense organs and which in turn illumine the various aspects of the creation. The Sun illumines the earth during the day and the Moon illumines the earth during the night.
There is a similar shloka in Kathopanishad 2:15. It says:
न तत्र सूर्यो भाति न चन्द्रतारकं नेमा विद्युतो भान्ति कुतोऽयमग्निः।तमेव भान्तमनुभाति सर्वं तस्य भासा सर्वमिदं विभाति ॥

There the Sun cannot shine and the moon has no luster; all the stars are blind; there the lightnings flash not, neither any earthly fire. For all that is bright is but the shadow of His brightness and by His shining all this shineth. Kathopanishad 2:15
ब्रम्ह स्वरूपम् or ब्रह्म लक्षणम् is continued.
Verse 62
The Brahman pervades the universe and shines like
a fire-permeated red hot iron ball

स्वयमन्तर्बहिर्व्याप्य भासयन्नखिलं जगत् ।
ब्रह्म प्रकाशते वह्निप्रतप्तायसपिण्डवत् ॥ ६२॥
स्वयम् अन्तः बहिः व्याप्य भासयत् अखिलम् जगत् ब्रह्म प्रकाशते वह्निप्रतप्तायसपिण्डवत् (वह्निः प्रतप्त आयस पिण्डवत्)
In the previous sloka, Acharya explained Brahman as devoid of all qualities. Such a nirvishesha Brahman is described here as Self-illumining. It is that because of which even the sun and moon are illumined. Understand that is to be Brahman.

स्वयम्-itself अन्तः-inwardly बहिः-outwardly व्याप्य-pervading भासयत् -illuminating अखिलम्-all जगत्-universe ब्रह्म-Brahman प्रकाशते-shines वह्निप्रतप्तायसपिण्डवत् (वह्निः-fire प्रतप्त heated आयस पिण्डवत्-red hot iron ball) like the fire permeating a red hot iron ball.
The supreme Brahman pervades the entire universe outwardly and inwardly and shines of itself. It is like the fire that permeates a red-hot iron-ball and glows as if it is fire.

स्वयम् अन्तः बहिः व्याप्य भासयन् अखिलम् जगत् – Brahman pervades everything inside and outside. It pervades our internal world- body, mind and ego. It pervades the external world of objects that we can see or fail to see. Brahman is the transcendental truth which shines of itself and penetrates the entire world of creation. It is not something other than the world of creation, for it exists in and through all as the Consciousness.
The consciousness principle not only pervades the entire outside world but also our inner world. All the emotions, feelings and thoughts are illumined by the light of consciousness and so we can cognize emotions like kindness, anger, hunger, love, hatred etc. He also illumines our knowledge and ignorance.
Gita says the same in 15.12 as:
यदादित्यगतं तेजो जगद्भासयतेऽखिलम् ।
यच्चन्द्रमसि यच्चाग्नौ तत्तेजो विद्धि मामकम् ॥१५:१२॥

The light of the sun which illumines the whole world, the light from the moon and light in the fire—know this radiance to be mine.

The famous sloka of Mundaka Upanishad 2.2.10 proclaims this as:

न तत्र सूर्यो भाति न चन्द्रतारकं नेमा विद्युतो भान्ति कुतोऽयमग्निः।तमेव भान्तमनुभाति सर्वं तस्य भासा सर्वमिदं विभाति ॥

There the sun does not shine, nor the moon or the stars; nor do these flashes of lightning shine there. How can this fire do so? Everything shines because he is shining. All this shine by his light.

The same is also explained by Lord in many places in Gita such as in 15.6:
न तद्भासयते सूर्यो न शशाङ्को न पावकः |
यद्गत्वा न निवर्तन्ते तद्धाम परमं मम || 15.6 ||
That the sun illumines not, nor the moon, nor fire; That is My Supreme Abode, to which having gone none return.

Whenever we see any object like a pen for example, we can see it due to two inherent things in it: one, is its existence (सत्) and the other is its knowledge (चित्). When we see an object, we are not aware of these two phenomena. We take it for granted. These two are representation of self.
ब्रह्म प्रकाशते वह्निः प्रतप्त आयस पिण्डवत् – The consciousness glows like a red-hot iron ball. Acharya gives the example of a fire ball to explain the role of consciousness.
The iron ball represents creation, and the heat represents the Self. It is the Self that imparts vibrancy and a glow to the iron ball and by implication to all creation.
A cold iron ball is a dull, unattractive object. However, when in contact with fire for a long time it comes to glow as fire itself. Similarly, the inert and insentient matter like the sun and moon also acquire their illuminating power due to the presence of Brahman.
In Vedanta light is that principle in whose presence external things and objects and internal feelings, thoughts and emotions are known and, in whose absence, these are not known.