What is Permanent ?
Bhagavad Gita: Chapter 2: Verse 16
The unreal has no existence, and the Real never ceases to be; the reality of both has thus been perceived by the seers of Truth.
How can Reality be known?
In this verse, Supreme Lord Sri Krishna, refers to two opposite concepts of real and unreal. It is important to understand the meaning of these two words in the context of the life process. It is to be understood that whatever is real is permanent, and whatever is unreal is temporary. The real does not undergo any change and it is the very cause for change. The real is that which instigates change. The real is unseen and cannot be perceived through the senses. It can only be realized if intelligence is purified and sharpened through sadhana. This reality is not the substance but the substrate of all happenings. If the real were not to be present or existent, there would be no scope to sense the unreal. The environment changes, the weather changes, the body changes but it is also a matter of perception that these ever changing entities occur in the light of something which does not change. Many generations have come and gone. Present becomes Past and Future transforms into Present but this change is noticeable and perceived. Perception can happen only if there is a point of reference. For example, we travel in a car and assuming that we get involved with the scene outside, it appears that the scene is traveling in the opposite direction. Now who can say whether the car is moving or the scene is moving? The reality of the situation can only be gauged by someone who is stationery and does not move. A person standing outside can only determine that it is the car that is moving and not the scenery. The same can be said about the rotation of the planets around the Sun; unless there is something that is considered as an Absolute frame of reference, one can never locate from where any change is being initiated. All observable phenomenon changes and this change is detected only by the entity that is changeless and that changeless entity is the unchangeable Reality. Reality is not definable on its own, it is only inferred from that which is changing. It is to be understood that all that is unreal has no separate existence. It is just transformation of energy from one form to the other and noticed by the real. Without the real, the unreal would have never existed.
Bhagavad Gita: Chapter 2: Verse 17
Know that alone to be imperishable, which pervades the universe, for no one has the power to destroy the indestructible substance.
What is the nature of Reality?
In the light of Reality, the unreal appears. The apparent unreality is just the shadow of Reality and has no separate existence of its own. Our bodies undergo constant change, times change and the way people behave change. It is in the light of consciousness that the whole dance of life occurs. Consciousness is that reality which is unaffected and that which is imperishable. Consciousness cannot be perceived but it is that in which perception takes place. It is the shadow of consciousness which is the body, mind and the universe. Just as in a dream, we see ourselves and others. We see, feel, smell, hear and taste in dreams. These transformations that are experienced are simple transformations within consciousness and it is consciousness alone that perceives these transformations. All experiences which includes our dreaming and waking states are unreal. They simply happen in the light of consciousness where consciousness is the subject, the experiencer, that which is real, and that which is experienced is the unreal and changeable or transformable. Consciousness is permanent and it is the substrate of the universe or even the multiverse, if it were to exist. It is that entity where there can be no change and hence it is indestructible. It is imperishable and the supreme subject. Once this becomes a realization, one will start moving towards permanence and imperishability not in terms of body or mind but in terms of knowing and towards destruction of all fear which is associated with change.
Bhagavad Gita: Chapter 2: Verse 18
All these bodies pertaining to the imperishable, indefinable and external soul are spoken of as perishable.
All possessions of Consciousness are perishable
That which animates the body is only that one consciousness. Consciousness by itself is only one. There cannot be several categories of Consciousness. It is like this. When the Sun is shining in the sky and there are several thousands of pots of crystal clear water placed in the open, the sun casts its reflection in the water of these various pots. Now the sun reflected in the several thousand pots cannot be said to be several, it is the one Sun that is shining brightly outside the pot, which seems to animate in thousand ways in the water contained in the pots. Similarly consciousness is only one and it is in the light of this single point of consciousness that living entities appear and disappear animating that single consciousness. Although a person, a Jeeva dies, his body is said to be invested with several unseen and minute living entities which are animated by the same consciousness. The representation of that one consciousness has withdrawn itself and has decided to handover the body to the other bodies which have been animated by the same consciousness. If one does not deal with the dead body, it shall decompose and decay on its own, consumed by other minute living entities or else other superior living entities animated by the same consciousness shall cremate the body and dispose it off thus. Hence consciousness presents itself in various sizes, forms and numbers. Yet for a man of high intelligence, it is realized that it is that one consciousness alone that has been transmuting and transforming itself, creating the illusion of change, growth and decay. It is only an intelligent man, who is able to see with realization that it is all the play of one life or one consciousness in the grand scheme of things and that includes him too. Hence the bodies, mind, intellect, memory are perishable and all of these belong to that one imperishable and eternal consciousness alone which never changes.