ज्ञेयं यत्तत्प्रवक्ष्यामि यज्ज्ञात्वामृतमश्नुते | अनादिमत्परं ब्रह्म न सत्तन्नासदुच्यते || १३ ||
jñeyaṁ yat tat pravakṣyāmi yaj jñātvāmṛtam aśnute anādi mat-paraṁ brahma na sat tan nāsad ucyate
jñeyam—the knowable; yat—which; tat—that; pravakṣyāmi—I shall now explain; yat—which; jñātvā—knowing; amṛtam—immortality; aśnute—one attains; anādi—beginningless; mat-param—subordinate to Me; brahma—Brahman; na—neither; sat—cause; tat—that; na—nor; asat—effect; ucyate—is said.
“I will now declare what is to be known — knowing which one attains immortality. It is the beginningless Supreme Brahman, which is said to be neither existent (sat) nor non-existent (asat).”
The object of knowledge (jneya) is declared: the beginningless Brahman. The striking phrase 'na sat tan nasad ucyate' — 'it is neither said to be existent nor non-existent' — reflects the Upanishadic understanding that Brahman transcends the duality of being and non-being as we ordinarily conceive them. Brahman is not an object that 'exists' (that would limit it); nor is it nothing. It is the ground of being itself, prior to the distinction between existence and non-existence.
The Absolute is described as beyond the categories of 'is' and 'is not.' This should shake loose any fixed concept of what the Divine is. Whatever you think God, Truth, or Reality is — the Gita says it is beyond that. The practice of 'neti, neti' (not this, not this) — releasing each concept of the Absolute — is itself a movement toward the Absolute.