8.18 - Bhagavad Gita - Chapter 8, Verse 18

Verse 8.18 of the Bhagavad Gita unlocks a profound vision of the vast, cyclical nature of the cosmos, as described by Krishna to Arjuna. Here, the cosmic day and night of Brahma—the most exalted being in Hindu cosmology—become the framework for understanding the creation and dissolution of the material universe. As Brahma's day dawns, all living beings and things arise from a subtle, unmanifest source, stepping into existence and activity. With the arrival of his night, this entire creation dissolves, merging back into the unmanifest, awaiting the next cycle of emergence.

This rhythm is not a simple alternation of sunrise and sunset as experienced on earth, but a cosmic oscillation spanning billions of years. Each day and night of Brahma stretches across what humans might perceive as an unimaginable expanse—yet even this is but a fleeting moment when compared to eternity. The magnitude of Brahma’s cycle sharply contrasts with our ordinary sense of time, underscoring how reality at the grandest scale is guided by forces and timeframes vastly beyond human perception.

Krishna’s teaching in this verse focuses on the impermanence of all created things. Even the grandest entities—celestial bodies, planets, and the very cosmos—cannot escape the cycle of becoming manifest from the unmanifest and returning to it again. All living entities, without exception, follow this recurring journey: emerging during cosmic dawn, acting through the day, and dissolving into potentiality at cosmic dusk.

This illustration makes clear that the material universe is not a single, linear progression but a series of repeating cycles. The visible, tangible world has its origin in the unmanifest, a subtle state beyond ordinary perception, which then expresses itself in myriad forms. These forms, whether they are galaxies or living beings, are all fated to dissolve back into the same source at the conclusion of the cycle.

The verse also subtly points to the distinction between the manifest and the unmanifest. What we perceive as real and permanent is temporary, bound to dissolve and be recreated again and again. The substance underlying these changes—the unmanifest reality—remains constant, while forms appear and disappear like waves on the surface of the ocean.

Krishna’s words serve as a reminder that all material accomplishments, identities, and relationships are subject to this cosmic law. When we expand the horizon of our awareness to encompass these cosmic cycles, our sense of attachment to transient things dissolves. The apparent solidity of the material world gives way to an understanding of its ephemeral nature.

Through this lens, even Brahma—the creator of the universe—is subject to birth and dissolution. The life span of Brahma, though seeming almost infinite to us, is still measured and limited, highlighting that impermanence is woven into the fabric of creation itself.

Ultimately, this verse invites the seeker to contemplate the ultimate reality that lies beyond both the manifest and the unmanifest: a changeless principle that is not affected by cycles of creation or destruction. Krishna offers this perspective not as a cause for despair but as an opening to seek that which is truly eternal, anchoring life’s journey not in the fleeting waves of material existence but in the steady, unchanging spiritual truth.