Verse
कर्म ब्रह्मोद्भवं विद्धि ब्रह्माक्षरसमुद्भवम् ।तस्मात्सर्वगतं ब्रह्म नित्यं यज्ञे प्रतिष्ठितम् ॥
From food creatures come into being, from rain is the birth of food, from sacrifice comes into being the rain, sacrifice is born of work; work know to be born of Brahman, Brahman is born of the Immutable; therefore is the all-pervading Brahman established in the sacrifice.
Gītā 3·15