Bg. 13.3

क्षेत्रज्ञं चापि मां विद्धि सर्वक्षेत्रेषु भारत ।
क्षेत्रक्षेत्रज्ञयोर्ज्ञानं यत्तज्ज्ञानं मतं मम ॥ ३ ॥

kṣetra-jñaṁ cāpi māṁ viddhi
sarva-kṣetreṣu bhārata
kṣetra-kṣetrajñayor jñānaṁ
yat taj jñānaṁ mataṁ mama

Synonyms
kṣetra-jñam — the knower of the field; ca — also; api — certainly; mām — Me; viddhi — know; sarva — all; kṣetreṣu — in bodily fields; bhārata — O son of Bharata; kṣetra — the field of activities (the body); kṣetra-jñayoḥ — and the knower of the field; jñānam — knowledge of; yat — that which; tat — that; jñānam — knowledge; matam — opinion; mama — My.

Translation
O scion of Bharata, you should understand that I am also the knower in all bodies, and to understand this body and its knower is called knowledge. That is My opinion.

The field of activities, an individuals karmic synchronicities, as well as their responses from a responsive universe, i.e.,an individual life . 8,400,000 different species throughout the fourteen planetary systems of this universal system.
Can you understand one persons life , how the body came to be , how it is maintained, and how you understand the psychological effects and the workings of an intelligence ? In reality, we do not understand how our fingernails grow .
Yet here God , or Krishna, declares that he is the knower of all bodies, not just humans. He is fully conscious of everything any creature feels or desires and through His direct agencies He is providing. The life experience is a complicated matter , especially when karmic reincarnation is operating. The whole universal machine is so far beyond our comprehension that we conclude that a person can not be behind it . Yet today, we accept the existence of complex algorithms . If we think of an intelligence as powerful and big as the sun , and Einstein’s like a firefly , we may get some idea of Divinity.
He leaves His intelligent traits everywhere.
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