Up to the 24th verse, Lord Krishna dealt with all the six topics Arjuna wanted to know.  From verse 25 to 27, Lord Krishna talked about the sadhanas required to gain this knowledge, the culmination of this knowledge should be knowledge.  Problem of samsara is because of the error with regard to the perception of ourself or self-error.  Through the knowledge, self-delusion goes away, with that samsara also goes away.  From 28on wards, Lord Krishna talks about benefits of this knowledge. 

First benefit is complete understanding of the world or säma darshanam:  Universe is a mixture of purusha and prakriti; every human being is also a mixture of purusha and prakriti; our vision will be right vision only if our vision is balanced with purusha and prakriti.  The prakriti part is physically visible whereas the purusha part being nirguna nirvikāra sathya chethana tatvam, will not be visible for physical eyes and it has to be appreciated with our jñāna chakshu.  Prakriti is useful in all our daily transactions but will not give poornatvam.  Purusha alone can give poornatvam.  Therefore, we need a balanced vision of purusha and prakriti. The first benefit of jñānam is säma darshanam – proper vision – understanding that universe is a mixture of purusha and prakriti. Raga Dwesha weakens säma darshanam

Verse 29

For, uniformly seeing the Lord who dwells everywhere alike, he does not ruin himself by himself.  Thereby he attains the supreme goal.

Purusha is the supporter of prakriti. Just as without the support of screen, movie can’t exist, prakriti can’t exist without purusha.  A wise person sees purusha all the time, but this jñāni does not destroy himself.  This is the second benefit – immortality.

How does a person destroy himself? A person kills both lower nature and higher nature.

First, a person destroys himself by identifying himself with the body; once you identify yourself with body, you become a kartha or doer as a kartha I perform variety of actions earning pavam and punyam.  These punyam and pavam are the reasons for creating a body.  Both the arrival and departure of body is the result of my karma. I alone am responsible for repeated birth and death.  I destroy my own lower nature again and again.

Secondly, by identifying with the body, one also kills one’s own higher nature – figuratively killing atma, by not being aware of higher nature, one disowns one’s own higher nature.  The benefits available by higher nature are lost and since I am not enjoying the benefits of higher nature, it is as through higher nature is absent.  Since it is as though higher nature is absent, we have killed or destroyed the higher nature.

Every ajñāni destroys himself from the standpoint of body as well as Jñāni.  A Jñāni does not destroys himself from either perspective.

Verse 30

He who sees all actions as being done by prakriti alone by all means, and likewise sees the self to be action less alone really sees.

The third benefit is akartatvam or understanding that I am not the doer.  A kartha will be eternally associated with karma.  Karma will get converted into favorable and unfavorable conditions.  If I am a kartha, then I can’t escape being a boktha and that is a choiceless, helpless situation. 

All actions are done by prakriti – body/mind complex or śarīram.  It is impossible to escape the cycle of arrival and departure of karma, the only way is to stay away from the cycle.  Prakrithi can’t be stopped; the only way is to transcend from prakriti is by identifying with higher nature. 

Vedanta should not be used for promoting adharma; a person should not use this verse to do adharmic activities, claiming all the activities are not done by “me” only by my lower nature, the body/mind complex.

Verse 31

When one sees the diversity of beings to be based on the oneself and their origination to be from that Self alone, then one becomes Brahman

Understanding atma must be done in many steps.  We take the example of space and a hall. 

• In a hall, there is hall and space inside the hall.  So, there is space and a hall. 
• Then, we see that there are many halls, and there is space in all those halls. 
• Then we see that the space within them is not many but one and the same.  Halls are different, but the space is not different. 
• Then we see that the space is not only within the hall, but there is also space outside the hall. 
• But really speaking, space is not inside or outside the hall, but there is only one space, and all halls are resting in it. 
• Finally, we realize, space is not only supporter of all halls, but all the things are born out of space. 

This example should be extended to atma.  Space should be equated to consciousness and the hall should be equated to body:

1. There is a body and consciousness.  The consciousness is within the body
2. Then we see there are many bodies and consciousness is within all other bodies also.
3. But the consciousness within our body as well as everyone else’s body is the same.
4. Consciousness is outside all the bodies also.
5. But really speaking, consciousness is not inside or outside, but consciousness is everywhere, and all the bodies are residing in consciousness.
6. Really speaking everything arises out of consciousness.
7. That consciousness is I am.

Krishna points out that this knowledge is a liberating knowledge.  A person who knows that body mind complex is prakriti and that I am purusha.  Body is prakriti and mind is prakriti; the association of mind and body is birth and dis-association of mind and body is death; they are all happening at the level of prakriti.  There is no question of one birth, then where is the question of rebirth.  A Jñāni who realizes this and knows that he is anädi purusha, does not have rebirth and gets moksha.

Verse 25

Some seekers see the Self in the mind with the mind through meditation.  Some others see through Gyana yoga.  Still others see Karma Yoga.

In verse 25 to 35 Krishna discusses the preparations needed for self-knowledge and what are the benefits of self-knowledge.

The ultimate goal of all spiritual sadhanas is self-knowledge only.  There should not be any doubt regarding this goal.  We should discover atma within ourselves, using our own buddhi.  Buddhi is the only instrument to get knowledge.  But this buddhi should be a refined buddhi supported by guru sastra upadesa. 

Preparatory stages for reaching self-recognition through the mind within oneself, five stage preparation helping in removing one obstacle in each stage:

1. Karma yoga stage, where mental impurities are removed. Impurities like raga, dwesha, kama, moha etc.  Karma yoga removes impurities and refines the mind.
2. Upasana or meditation upon saguna Eeswara; Removing the obstacle of restlessness of mind and extrovertedness; helping mind to focus.
3. Vedanta Sravanam:  Systematic and consistent study of Vedantic scriptures under the guidance of a competent guru, removing ajñānam or ignorance.
4. Mananam:  Asking myself if I am convinced of the teaching of the scriptures and guru.  Converting knowledge into conviction; removing intellectual obstacles.
5. Nidhithyasanam:  Deliberate invocation of Vedanta to get rid of disturbing reactions of life.

These five stages are compulsory for all.  If one does not complete all five stages in one life, the remaining stages are completed in the next life.  The one who passes through the four stages and in the next life goes through nidhithyasanam, resulting in spiritual prodigy. 

Verse 26

Not knowing thus, some others pursue self-knowledge by hearing from others.  Being committed to listening, they also definitely cross over mortality.

Vedanta does not require any particular scripture but insists upon the vedantic teachings.  Vedanta does not refer to language, but only the teachings and the contents.  If a person who doesn’t know the Upanishad but has assimilated the teachings, he is liberated.  However, if one goes through all the upanishad, but does not assimilate the teachings, he is not liberated.

Verse 27

Whatever being, moving or stationary, is born – know that to be out of the union of shethragya and kṣetram – oh Arjuna!

For preparation and purification of mind, there are many sadhanas, but for mokśa there is only Jñānam.  Samsara is caused by ignorance and error.  We are ignorant of the fact that we are purusha or atma.  Identifying ourselves with the body or prakriti or anatma is error.  Self-ignorance leads to body identification.  I, the consciousness take ourselves to be the body.  I, the immortal purusha mistake myself to moral body.  Apūrṇathvam leads to kāma; Kāma leads to karma, karma leads to punya päpam, punya päpa leads to sukha duḥkam, and later to punar janma. In fact, entire cycle of birth and death is dēha abhimāna. All beings go through re-birth because of this error and the cause of the error ignorance.  To remove the error, we need to remove the cause, and the cause is ignorance.

Verse 28

He who sees the supreme Lord who dwells alike in all being and who is imperishable among perishables (alone really) sees.

From this verse onwards, Lord Krishna enumerates Jñāna phalāḥṃ.  The first one mentioned is to be aware of changeless atma which is in and through all anatma.  Just as there are numerous waves, there are innumerable anatma, which are different from each other.  Among these innumerable bodies, there is on imperishable sat chit atma or paramatma.  Wise person is the one who does not lose sight of this fact during day-to-day transactions.  If I am aware of the permanent one, I will handle the impermanent one but will not depend on the  impermanent one. 

Lord Krishna has come to the last pair of topics, purusha and prakriti.  Purusha and prakriti are two basic principles that existed even before the creation of the world, and this mixture of purusha and prakriti is called God.  The common features of purusha and prakriti are both are anädi and both of them can’t be the cause of creation alone.

Uncommon features or difference between Purusha and Prakriti are:

1. Purusha is chethanam and Prakriti is achethanam.
2. Purusha is nirvikāram.  Prakrithi is savikāram.
3. Purusha nirgunam; Maya is sagunam.
4. Purusha sathyam; Prakriti is mithyam.

Everything is prakriti and purusha is available behind the body mind complex and available as the witness.  Whatever is experienced or witnessed is prakriti or the object of experience.  The body mind complex falls under prakriti or the object of experience.  The body mind complex is used as a medium to experience and witness and as a result often mistaken for Purusha or I.  The body mind complex used as an instrument, appears as subject.   World is prakriti, mind is prakriti.  I am different than the world, mind and prakriti.  Illumining the body mind is not the activity of Purusha, but the body mind illumined by the very presence of purusha.    This is similar to sun.  Sun does not illumine the objects, the objects get illumined by the very presence of the sun.  Even the blank condition of the mind is also witnessed by the consciousness.  Transference of body mind complex attributes to I, the consciousness and witness, causes samsara.  This is similar to transferring the problems of a character in a movie to me, the audience.     

Verse 23

The supreme purusha in this body is said to be the proximate witness, the supporter, the sustainer, the experiencer, the great Lord and the supreme Self.

Krishna says purusha is in the form of witness everywhere.  The nature of this purusha is different than the prakriti. Lord Krishna gives more features of purusha:

1. Paraha:  Free from all limitations; The consciousness not only within the body, it is also extends beyond the body.  Eventually we must realize that we are inside the consciousness.  This is similar to space.  Space is inside the room, outside the room; but really the room is in space.
2. Upadhrishta:  The intimate witness of everything happening inside you.  Purusha pervades every cell of our bodies. 
3. Anumandhacha:  Purusha blesses inert body and mind and because of its blessing alone body is what it is. 
4. Bartha:  Purusha lends existence to everything in creation.
5. Boktha:  Purusha is experiencer from the standpoint of an ignorant person.  Seeming boktha, as though suffering from attributes.
6. Maheswaraha:  Purusha is ever free.  For a wise person, consciousness is a free entity.  Body and mind are bound by prakriti, but purusha is not. 

I am called jivatma when I take the attributes of prakriti, but when I take the attributes and understand that they don’t belong to me but to prakriti, then I am paramatma.  

Verse 24

He who thus knows purusha and prakriti along with the gunas, is not born again, in whatever manner he lives. This clear knowledge about prakriti and purusha will give a person great relief from samsara.  The initial knowledge is I am a mixture of purusha and  prakriti. I also know there are many physical attributes and subtle, internal attributes.   But these attributes belong to prakriti.   For all day-to-day activities, we have to identify with prakriti. But understand that the whole life is a series of role playing. But when role playing is taken seriously, it results in samsara.  A Jñāni who understands this, he will not have a punar jenma or re-birth.

With the 19^th verse, Lord Krishna has completed four topics out of six topics that Arjuna wanted to know.  The four completed topics are: kṣetram, kṣetrajña, jñeyam and jñānam.

From the 20^th to 24^th verse, Lord Krishna deals with Purusha and Prakriti.  Purusha is Brahman and Prakriti as Maya.  So, this discussion is Brahman and Maya.  Purusha and Prakriti are basic principles and are anathi; We call the mixture of purusha and prakriti as Eeswara.  Eeswara existed before shristi or the origination of the universe; so, the shristi must have come from Eeswara.

The common features of Purusha and Prakriti is that they both are beginningless and the both of them together created shristi, exactly like father and mother.

Uncommon features or difference between Purusha and Prakriti are:

1. Purusha is chethana tatvam or consciousness principle and Prakriti or Maya is achethana tatvam or material or energy principle.
2. Purusha is nirvikāra tatvam – not subject to time and modification, ever changeless principle.  Prakriti is savikāram or subject to change and the influence of time.
3. Purusha is free from all attributes; nirguna tatvam; matter or Maya is endowed with all attributes or saguna tatvam.
4. Purusha has an independent existence and is satya tatvam; it is intrinsic.  The matter principle depends on consciousness principle, and it is called mithyam.

The purusha prakriti mixture called God was there before the existence of world.  We will not be able say where God was located, because before creation, even akasha or space was not there.

Nothing happens to purusha tatvam and will remain the same.  All the changes must happen to prakriti, the basic matter or energy principle.  The universe evolves from this prakriti principle.  All the products are born out of this prakriti or maya.  Initially the five basic elements were born, and later through these five elements, all other matters were born.  Our physical body is also an evolved prakriti, because the body is matter and made up of chemicals and elements.  The body is nothing but a chemical bundle and is subject to modification.  Therefore, the body is a product of prakriti.  The mind is also the product of prakriti, subject to change.

If both mind and body are born out of prakriti, then they both must be insentient. But they appear to be sentient.  That is because they are refined version of prakriti, they are able to reflect borrowed consciousness. 

Not only all the objects are born out of prakriti, all the properties of objects are also born out of prakriti.

Verse 21

Prakriti is said to be the cause in the creation of the physical and subtle bodies.  Purusha is said to be the cause in the experience of pleasure and pains.

Everything in the universe is born out of prakriti, including body mind complex.  If everything is product of prakriti, where is purusha?  Experienced world is prakriti; experienced body is prakriti; experienced mind is prakriti; If everything is product of prakriti, where is the purusha?  If you look for purusha outside, everything outside is subject to change, so it is prakriti.  If you look for purusha within the body, body is also subject to change, so it is prakriti.  Inside the mind, the thoughts are always changing, so it is also prakriti. 

Purusha is the experiencer, I, the basic conscious principle.  I am the witness of the world, witness of the body, witness of mind.  It is not an object, because all objects are subject to change and are prakriti. Purusha is boktha, the experiencer of body.  The body and the all conditions of body belong to  prakriti.  All the observed properties can belong only to the observed object and never to the observer.  The observer is always property free.

In the created world, prakriti is available as object and purusha is available as subject and purusha can never be objectified.  This is similar to how the eye can never see itself. If the eyes can never be seen, what is the proof of the existence of the eyes.  Because you don’t require proof of the existence of eyes, because every object seen is proof of the existence of eyes.  The subject does not require proof because the very search for proof proves the existence of the subject.

Verse 22

Residing in Prakrit, Purusha experiences the gunas born of prakriti.  Attachment to the gunas is the cause of birth in superior and inferior wombs.

Before creation, purusha was neither the subject nor the prakriti was object.  When did purusha get the subject status?  At that time consciousness was all pervading un-enclosed consciousness.  After the creation, consciousness was still all pervading but enclosed within the body mind complex.  The whole world becomes an object.  Purusha becomes the subject and prakriti becomes object.

In this chapter, Lord Krishna has come to the topic of jñeyam.  This word jñeyam is nothing but param brahma of Upanishad.  Param Brahma is the subtlest topic of Upanishad and Bhagavat Gita.  Param Brahma is nirgunam so is not available for sensory perception.  It is all pervading.  It is only one, Ekam.  The objects in the universe are many, but the subject is only one.  It is one but appears to exist only with objects – just like the light appears only when reflected by the finger not to be present in between fingers, but it is all pervading.  It is almost impossible to conceive such a Brahman.  You have to train to understand Brahman, one of the method prescribed is to meditate upon the word Akasa or space.  Because when you meditate on akasa, you don’t see, touch, smell etc.  Even though Akasa is not perceptible, tangible, only one and not divisible.  Space may mean emptiness, but it is not empty but a positive object.  But still we are able to talk about it.  Akasa dhyānam is prescribed to understand the subtle object, similarly, try to understand Brahman, which is even more subtle.

Verse 18

It is the light of all lights.  It is said to be beyond ignorance.  It is the knowledge, the object of knowledge, and the goal of knowledge, present in the heart of all.

The brahman is same as the atma or consciousness:

• Consciousness is not a part, product, or property of an individual.
• Consciousness is an independent principle, pervading the body and making it alive.
• Consciousness is not limited by the boundaries of the body.
• Consciousness survives the fall of the body.
• Surviving consciousness is not accessible because there is no medium.

That consciousness is the existence Brahman.  In Vedanta, light is defined as that in whose presence things are known and recognized.  From that standpoint all luminaries in the sky like sun, moon, lightning are all called light, because in their presence we recognize and know the objects.  Extending this principle, every sense organ can also be known as light, because objects are known only in the presence of sense organs.  Only in the presence of our ears we know the sound.  In the presence of eyes, we see the object.  Every instrument of knowledge is light.  The ultimate light is the consciousness principle, only in the presence of consciousness everything is known. If consciousness is not there, an inert thing cannot know anything.  If the light of consciousness is not there, then the sun, moon etc. becomes useless. Therefore, consciousness is called light of light, because in the light of consciousness alone all other light reveals other objects.  The light of consciousness is unique, because only in the light of consciousness you can know darkness.  Light can’t make you know what darkness is.  Consciousness is a unique light, because it can co-exist with darkness.  This formless existence consciousness alone appears as the formed universe.  Similar to when energy is converted into matter, It becomes tangible.  Nontangible Brahman alone is the cause of the universe.  That Brahman alone is the means of knowledge; the object you know is also Brahman.  The instrument is also Brahman.  You have to discover that Brahman only in your mind.  But we have no way of recognizing the consciousness in others.  But this consciousness is in everyone and also between everyone. 

The topics of kṣetrajña and jñeyam are one and the same principle.  The consciousness obtained in from micro standpoint is kṣetrajña and the consciousness from  the standpoint of macro is jñeyam. 

Verse 19

Thus kṣetram, jñeyam and jñānam have been taught briefly.  Knowing this, my devotee becomes fit to attain My nature.

In this verse, Lord Krishna consolidates the teachings of the four topics already discussed – kṣetram, kṣetrajña, jñeyam and jñānam.  Krishna also indicated that bhakti is an important factor in knowing this knowledge.  Without devotion, jñānam does not take place.  Without devotion, he may be an expert, but the knowledge will be academic. One who get this knowledge,  he will discover the eternal freedom, which is his very nature.  Poornatvam is the benefit of this knowledge.

Verse 20:

Know both Prakriti and Purusha and purusha to be beginningless.  Know all the products and gunas to be born of prakriti.

Verse 20 to 24 Krishna teaches purusha and prakriti; this is similar to kṣetram (matter Principles) and kṣetrajña (Consciousness principle).  Vedanta takes consciousness as an independent principle.  All objects are made up visible matter principle and invisible consciousness principle. 

In this 13^th chapter, Arjuna asked for clarification of six concepts:

1. Prakriti
2. Purusha,
3. kṣetram,
4. kṣetrajña 
5. jñeyam
6. jñānam

Krishna now addresses jñeyam or Brahman in verses 13 through 19^th.  In this context jñeyam means param brahman.  Jñeyam, Brahman is the ultimate truth everyone should know.

Krishna is revealing Brahman as pure existence.  Existence and consciousness are two subtle concepts which have different meanings than what we usually we think of.  According to vedanta, existence is the unique and all principles we talked about consciousness can be extended to existence.  All these five principles must be extended to existence also because existence is same as consciousness. 

1. Existence is not a part, product, or property of the body of any object.
2. Existence is an independent entity and is the ultimate substance, which pervades the body and makes it existent.
3. Existence extends beyond the body or object.
4. Existence survives the fall of the body or object.
5. The surviving Existence is not recognizable, not because it is not there, but because of the absence of reflecting or manifesting medium.

This pure existence is pure consciousness, that pure consciousness is Brahman, and that pure consciousness is you – Tat Tvam Asi.  Pure existence can never be understood – it can only be understood along with an object.  Similar to when you ask for water, it is understood that a cup is needed to transport water.

The existence’s manifestation is recognized through every sense organ.  In and through every sensory perception, existence is recognized. At the same time, the existence or Brahman is free from all the sense organs; they are not intrinsic nature of Brahman.  Similar to hand being not part of light.  You appreciate the world through existence, but world is not a part of Brahman.  This existence Brahman supports everything, because of Brahman alone every object enjoy existence.  Brahman is free from all the objects of the world. 

Existence is associated with every object, but not affected by any objects.  Similar to all characters of a movie are associated with the screen, but the screen is not affected by the characters of the movie.  Brahman is nirgunam.

Verse 16

It is outside and inside beings.  It is unmoving and moving.  It is far and near.  Being subtle, it is unknowable.

The existence Brahman is both inside outside the body and objects, similar to the light is upon the hand as well as outside the hand in unmanifested form.  Consciousness is in this body; consciousness is other bodies and consciousness is also in between the bodies.  You can never think of absence of existence anywhere. 

It is moving and it is nonmoving.  It is really non-moving, but it is seemingly moving when the medium moves.  Moving property of an object is transferred to existence.  For example, the rotation of the earth is attributed to the sun, and we say sun rises and sets, but the sun does not rise and set. 

For a wise person, Brahman is the nearest – is one with me.  For an ignorant person, Brahman is far away, because he continues the search for Brahman.  If Brahman is everywhere, why don’t I recognize that Brahman?  Even though Brahman is everywhere, Brahman is free from attribute, and we can’t recognize an object if it does not have any attribute.  Attributes alone help me recognize.  We recognize objects by color, form etc.  The less the number of attributes an object has, the more incomprehensible the object is. 

• Prithivi is the grossest thing we can recognize – it has all five attributes – smell, taste, sound, touch, and form.
• Water does not have the attribute of smell, but has the other four – taste, sound, touch and form. 
• Agni has three attributes – sound, touch and form, but does not have the attributes of smell and taste.
• Vayu has two attributes, sound and touch and not form, smell and taste.
• Akasa has only one attribute – sound, the echo capacity.

Verse 17

Moreover, it remains undivided.  Yet it appears as if divided in beings.  That Brahman is the creator, the destroyer, and the sustainer of all beings.

Brahman is indivisible, like space which can’t be divided.  At the same time, it is seemingly divided.  It is in every body, but also in between the bodies.

From the 13^th verse to 19^th verse, Lord Krishna is introducing the fourth topic, jñeyam.  The word jñeyam means that it is to be known by everyone, the ultimate truth of the universe.  Every human being wants immortality; therefore, everyone should know this truth.  This is brahma vidya. 

Verse 14

It has hands and legs everywhere.  It has eyes, heads, and mouths everywhere.  It has ears everywhere.  It remains pervading everything in the world.

In the Upanishads, brahman is defined as basic essence, the ultimate content of the universe.  All the sciences are also trying to find out the ultimate substance of the universe.  Initially, they thought that the whole universe is made up of combinations of elements.  Then they arrived at molecules; thereafter they said that all the molecules are made up atoms and the whole universe is invisible atoms in motion, creating a visible universe.  Thereafter, the scientists broke the atoms into particles and that was the ultimate substance.  Then they divided the particles, and they thought the energy is the ultimate substance of the universe.  As you go deeper, the visible becomes invisible, tangible becomes intangible; concrete becomes abstract.  Scientists have not yet arrived at the final answer.  But Vedanta has arrived at Brahman as the ultimate substance of the creation; being the ultimate substance, Brahman will be abstract, intangible, invisible with no form, sound, smell etc. Therefore, understanding Brahman will be difficult because it is not available for touching, smelling, or seeing.

We see lot of substances in the world like “a tall man”.  We use a noun and an adjective to describe a substance.  Adjectives reveal the property of an object.  Nouns reveal the substance.  Let us take the example of a golden bangle or a wooden chair.  Bangle is noun and golden is adjective.  The word golden does not refer to the property but the very substance of the bangle.  Gold is the substance of the bangle.  In this case, adjective reveals a substance but not a property.  In the example of a tall person, tall reveals a property.  An adjective can reveal either a property or a substance.  Bangle is a noun, but it does not reveal a substance, because there is no substance called bangle.  There is only a substance called gold.  Then what does the word bangle refer to?  When the gold is in a particular form or shape, then that shape alone is called bangle.  Bangle is only the form or shape of the substance; the name of the substance is gold.  Bangle is the name of the form only and the form is changed when the gold is melted.  Adjectives reveal property or substance.  Nouns can reveal adjectives or property.  Examples:

• Adjective revealing Property:  Tall
• Adjective revealing Substance:  Golden; wooden.
• Noun revealing Substance:  Tree
• Noun revealing the property: Bangle, chair.

When I experience the world, for example, there is a wall.  The verb “is” points to existence.  Examples are there is a tree, there is a man.  Everything you experience in the world is an existent object.  If anything is non-existent, then we will not experience it. 

What is the noun and adjective in the sentence “there is a man”.  The word existent is adjective and man is the noun.  What type of adjective and noun it is?  An adjective can reveal a substance or property; The word existent adjective reveals the property or the substance?  Until we come to Vedanta, our conclusion is that the world is the substance and the word existent is an attribute or property.  Vedanta says that is the work of Maya.  Maya makes you commit a big mistake of making you think that the existent adjective is not revealing the attribute, but the substance or according to Vedanta, Sat Brahma.  Existence is the fundamental, absolute substance and as a result is invisible, intangible and abstract, without form or any other property. 

If the adjective reveals a substance, according to Vedanta, every noun reveal a property; bangle is not the substance, but the shape of the gold, substance is gold.  The whole world is not a substance at all but a different name and form.  Existence is the only substance.  When you are experiencing different objects, you are experiencing the fundamental substance; when you are experiencing a chair, you are experiencing the wood. So, when you experience world, you are experiencing the basic substance, existence, Brahman.

You are experiencing the basic substance, the existent with different name and form; existent is never experienced in pure form, but only with a name and form through my sense organs.  Sense organs are equipped to experience only substances with properties – shape, name, smell, taste etc.  How can I experience pure existence?  When you remove all the name and form, what is left behind is pure existence.  But the sense organs can never experience the pure existence.  To experience the ultimate substance, close all your sense organs, what is left behind is basic substances which is pure existent.  How do you experience the pure existent without any sense organs?  You can never experience pure existent because it is not an object of experience.  Then how do I know it is there?  It is you, the witnessing consciousness. Pure existence is nothing but pure consciousness and that is me, the existent consciousness.

The example given in the Upanishads is dream experience. A dream is capable of frightening you, but when you are in dream, you are the essence of the dream world, the dream world is resting on you and on waking up the dream will go away,  When you are in dream, it is very difficult to accept that.  But when you wake up, the dream world will not exist. It is difficult to accept that the dreamer is the substance.  During the dream it is difficult to accept that I am the dreamer.  Similarly, it is difficult to accept that I am the substance of the world.  That “I” is Brahman and that Brahman is existent and that Brahman alone appears with different nama roopa. Just as gold is inherent in all ornaments, existent is inherent in all objects.  If an object does not have existence, it is a non-existent object.

Verse 15

It is manifested through the functions of all organs.  Yet it is free from all organs.  It sustains everything.  Yet is unattached.  It is the experiencer of gunas.  Yet it is free from gunas.

All the sense organs reveal Brahman all the time.  Eyes can reveal only color, but not sound.  Ears can only reveal sound but not color.  All the sense organs experience one thing in common, that is existence.  They all reveal uniformly Brahman.  But we are attracted by nama roopa and lose sight of the inherent existent substance, Brahman.  But due to the mixing up of nama roopa, we miss the substance.

Lord Krishna is dealing with the topic of jñānam from verses 8 to 12.  In this context jñānam means all the virtues of mind which are conducive to the attainment of knowledge.  In the 11^th verse, Lord Krishna emphasizes the importance of Bhakti.  Jñānam is only possible with the bhakti.  Karma yoga, upasana yoga and jñāna yoga all are bhakti yoga.  When Krishna prescribes bhakti as a necessity, it is not jñāna bhakti as this is a sadhana to becomes a jnani.  Artha bhakti is only conducive for worldly goals.  Here the goal is God and not a means to worldly end.  So, this bhakti can only be jigyasu bhakti.  We should have the maturity enough to know that everything other than God is perishable and god alone can give me security and completeness.  This devotion to God must be undivided.  Even when the worldly transactions are going on, this devotee must remember that the purpose of life is poornatvam. 

The next virtue are.

1. Viviktha desa sevitvam:  Resorting to a secluded place; resorting to solitude; this is also expression of samsara; Developing a habit of going to a secular place of solitude and find out whether I can confront myself.  One version of samsara is the fear of solitude or loneliness   This is the other purpose of this solitude is to face loneliness.  This will also help to gracefully handle old age.
2. Tattva jñānam artha darshanam:  Knowing value for Jñānam; knowing the benefit or the value of Jñānam. We should know what we will get out of this knowledge.  Regularly remind us that jñānam gives inner peace and inner freedom.
3. Adhyatma Jñāna nithyātvam:  Systematic and consistent study of Vedantic scriptures for a length of time under the guidance of a competent acharya.  Without systematic study, we will get only a few ideas.  The word sravanam presupposes study of the scriptures under a competent acharya.  This guru should deal only with sastra.  All other virtues prepare the student and this virtue provides the knowledge.

These 20 virtues together with satvic study will lead to gyanam.  Opposite of all these virtues is ajñānam.  Negative virtues will solidify ignorance. 

Verse 13:

I shall teach you that which is to be known, upon knowing which one attains immortality.  It is the supreme Brahman which is beginning less.  It is said to be neither and effect nor a cause

Arjuna wanted to know about six topics.  Now Krishan takes up the topic of Jñeyam in verse 13 to 19. Jñeyam is same as kṣetram. This subject matter everyone should know because this solves the fundamental and universal problem of insecurity that every human being suffers.  The ultimate thing to be known is brahman.  Brahman is free from three limitations:

1. Space limitation (can only be in one place),
2. Time Limitation.  We have a date of birth and date of death.
3. Attribute limitation.  Presence of one attribute, excludes all other attributes; One color excludes all other colors.

Brahman is free from all the three limitations; Any cause is in potential form, but it is not available for use,  so  it is as though does not exist, and it is called asat.  Everything we see and experience is the result of cause-and-effect flow.  The difference between kariyam and karanam is time.

Brahman is beyond time, space and attribute and is beyond the realm of cause and effect.

In verses 8 to 12, Lord Krishna is dealing with jñānam.  Jñānam is a set of virtues that indicate the level of mental health.  This mental health is useful to enjoy a peaceful mind and is required for a vedantic student.  If the mind is not healthy, the intellect will be a hostage of sick mind.  A disturbed mind will suppress intellect.  Mind is healthy when these virtues are followed.

1. Vairāgyam:  Mastery of sense organs.  Mastering Jñānendryani, which receives input from the world and mastering Karmendrayani which transact with the world.  
2. Indriyasthesu; Mastery form sense objects.  Controlling sense organs requires being alert all the time because these sense organs come in contact with sense objects on a regular basis and these sense organs develop attachment to sense objects.  You are allowed to enjoy pleasures without becoming a slave to those pleasures.
3. Anahangarah:  Freedom from arrogance, vanity, pride; humility;  Different than amanithyam; Amanithyam is freedom at the thought level; Anahangara is freedom at the verbal level; Adhambithvam is at physical level.
4. Don’t be body-oriented life:  This will lead to sorrow related to pain in birth, old age, disease and death.  This doesn’t mean neglecting the body, but remembering it is only an instrument.  Constantly remember pain related to these dosha.
5. Asakthi:  Mental or inner detachment, avoidance of mental slavery with regard to any external objects.   Dispassion through discrimination and not by suppression.
6. Anabishishvangaha; Absence of excessive attachment with child, spouse, house etc.; things with which we move constantly.  Attachment to these can’t be avoided, but we should avoid excessive attachment.  Attachment is mamakara, excessive attachment is when I become one with that object and don’t see any difference between that object and me. 
7. Samacit tatvam:  Being equanimous; this is the essence of karma yoga.  Freedom from elation and depression of good and bad situation.  Don’t be carried away in good and bad situations.   Every human being will have favorable and unfavorable situations.  Spiritual growth requires suffering also. Accept every experience as eeswara prasadham for my spiritual growth. 
8. Ananya Yogana:  Bhakti; There is no question of secular karma yoga; karma yoga presupposes faith in God or bhakti.  Prasadham means tranquility of mind; accept everything as a prasadham from lord.  This is possible only when there is devotion to the Lord.  Without bhakti and devotion, there can’t be karma yoga.