With imagery taken from the Katha Upanishad, Krsna portrays the entire universe as the Asvattha or pipal tree with root above and branches below. The root is Brahman, God, the branches are the manifestations in the world. The secondary roots that emerge from the main root are the vasanas, ignorance. The branches are activities that go upward, take you toward evolution, or downward to degradation. In this chapter, Krsna urges you to cut apart this firmly rooted tree of the material world with the weapon of detachment.
In this short yet immensely deep chapter, Krsna expounds the nature of Brahman and how It pervades the manifested world. Brahman is self-effulgent and is not illumined by the sun, moon or fire. He describes Brahman as a trinity of ksara, aksara and Uttama Purusa – perishable, imperishable and the Supreme Spirit.
Krsna begins with the ksara, perishable aspect of Brahman. The ksara consists of the external universe and the individual. Brahman is the very core of both the universe and the individual, you. He reinforces the thought that you are the Spirit acting through matter equipments. When Spirit identifies with matter, prakrti, an individual is born. It attracts to itself the senses and mind and gets clothed in a physical body. When it enters and leaves the physical body it carries the vasanas, dormant desires, as well as the subtle body, mind and intellect. The ignorant fail to perceive the Truth and get tossed by the material changes in the world. Only the wise who see the underlying Reality experience lasting peace.
To dispel any false notions of Brahman being perishable, Krsna goes on to describe It as aksara, imperishable. Brahman is the imperishable foundation of the perishable world. As Brahman personified, Krsna says He is the splendour of the sun, the moon and fire. He sustains all beings with energy. He enters the earth and nourishes vegetation. He is the fire that digests the food eaten by all beings. “I am installed in the hearts of all” declares Krsna. Memory, knowledge and their loss arise from Me. The sorrow and pain of separation is mitigated by forgetfulness. This loss of memory is partial during our lifetime and complete on death. It is a great blessing as it lightens the burden of life which would otherwise be impossible to bear. It enables us to start afresh on the journey of life and discover the truths that lie hidden. Thus He sustains both the macrocosm, the universe, as well as the microcosm, the individual. In this portion, Krsna asserts that Brahman is the aksara, imperishable supporter of the perishable world.
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Finally, Krsna destroys any limitations you may have imposed on Brahman by saying It is not confined to the finite world. It is the Uttama Purusa, Supreme Being, far beyond the universe that we visualise. When you want to point out gold to a person who has never seen it how do you go about it? You show a gold ornament and say this is gold. The person’s understanding is restricted to the shape and size of the ornament. So you melt the piece and say the imperishable material with which the perishable ornament is made is gold. But he still has not understood gold for his perception of gold is only that little portion that has gone into the ornament. Gold exists beyond the ornament in its pure form. Thus it is necessary to bring in the third entity beyond the ornament and the gold that goes into its making.
The universe with its millions of galaxies is ksara, the perishable aspect of Brahman. The imperishable substratum of the perishable world is aksara. But the universe is still the reference point. The vast cosmos is only an infinitesimal disturbance in the immeasurable expanse of Brahman. Krsna thus has to bring in a third concept, that of Uttama Purusa or highest Self, to complete the picture. Beyond the ksara and aksara is the Uttama Purusa that pervades the three worlds of waking, dream and deep sleep and exists beyond, in Its pristine glory. With this Krsna completes the description of Brahman.
In essence Krsna says I am beyond the transient world and above the eternal foundation too. I am celebrated in the world and in the Vedas as Purusottama, supreme Being. The wise aspire for Me, setting aside the entire world and its fascinations. They worship Me whole-heartedly and become truly fulfilled. And it is they who become the Spirit.