यावत्सञ्जायते किञ्चित्सत्त्वं स्थावरजङ्गमम्। क्षेत्रक्षेत्रज्ञसंयोगात्तद्विद्धि भरतर्षभ ॥

yāvat sañjāyate kiñchit sattvaṁ sthāvara-jaṅgamam kṣhetra-kṣhetrajña-sanyogāt tad viddhi bharatarṣhabha

Whatsoever creature is born immobile or mobile, know thou, O best of the Bhâratas, that it is from the union between the Field and the Knower of the Field.

In plain words: Krishna tells Arjuna that every creature that is born, whether it moves or stays still, comes from the joining of the Field (matter) and the Knower of the Field (spirit).