Bhagavad Gita
8.3

श्रीभगवानुवाच अक्षरं ब्रह्म परमं स्वभावोऽध्यात्ममुच्यते । भूतभावोद्भवकरो विसर्गः कर्मसंज्ञितः ॥

śrī bhagavān uvāca akṣaraṃ brahma paramaṃ svabhāvo'dhyātmamucyate | bhūtabhāvodbhavakaro visargaḥ karmasaṃjñitaḥ ||

Translation

The Blessed Lord said: Brahman is the Supreme Imperishable. Adhyatma is said to be one's own nature (svabhava). Karma is the name for the creative force that causes the arising of beings.

Interpretation

Krishna answers three questions at once. Brahman is aksharaṃ param — the supreme imperishable, the absolute that never undergoes change or destruction. Adhyatma is svabhava — one's own essential nature, the deepest truth of what one is (the Atman). And karma is defined not as ordinary action but as the fundamental creative force (visargah) that causes beings to arise — the primordial act of creation, the emanation of existence from the divine ground.