Bhagavad Gita Chapter 3, Verse 11

देवान्भावयतानेन ते देवा भावयन्तु वः | परस्परं भावयन्तः श्रेयः परमवाप्स्यथ ||

devān bhāvayatānena te devā bhāvayantu vaḥ parasparaṁ bhāvayantaḥ śreyaḥ param avāpsyatha

By this yajna, nourish the gods, and may those gods nourish you. Thus nourishing one another, you shall attain the supreme good.

Krishna reveals cosmic reciprocity through yajna. When you nourish the greater whole, it nourishes you back—not as transaction but as ecology. Like breathing: you give CO2, plants give oxygen. The devas (natural forces, life-sustaining systems) thrive when you serve them through selfless action. This is parasparam bhāvayantaḥ—mutual flourishing through mutual contribution. Extraction depletes; reciprocity sustains.