Srimad Bhagavad-Gita :
Chapter-13. ( Kshetra-kshetrajna-vibhaga-yogam )
Slokam-3. ( arjuna! you should understand that I am also the knower in all bodies, and to understand this body and its owner is called knowledge. This is My opinion.)
kshetrajnam capi mam viddhi sarvakshetreshu bharata,
kshetrakshetrajnayorjnanam yattat jnanam matam mama.
bhatata! sarvakshetreshu api = arjuna! in all Kshetram-s (bodies);
mam kshetrajnam viddhi = know I am the Kshetrahnan;
kshetrakshetrajnayo = about Kshetrajnan;
yat jnanam tat jnanam = knowledge is jnanam;
(iti) mama matam = this is opinion.
In the previous slokam-s after explaining about 'Kshetram and Kshetrajnan' here in this slokam, Lord declares :
"In all Kshetram-s I am the Kshetrajnan."
Then if it is one Kshetrjnan in all kshetram-s, what is the explanation for this world's diversity of its people ( Kshetram-s )?
Anatma-vastu-s manifest many only; their tattvam the one and only Paramatma itself.
It is not different from one, but it is sva-svrupam of each Sadhakan, and he must realise this by experience.
That is Me only ( Soham ) and this 'anubhuti' itself 'Atma-sakshatkam'.
Therefore, Lord declares : "in Sarva - Kshetram-s the insider, i.e, the inner chaithanyam is Me, the 'Kshetrajnan."
Lord now in the state of 'Yogarudan' i,e, one should not see Paramatma different / away from him, but in him itself.
"Electricity can claim that it blazes in all bulbs all over the world!"
After telling about the above details, Lord says : that 'Jnanam' is is the knowledge of this tattvam i.e, "Khetram and Kshetrajnan".
Body-s etc are not permanent, should be deposited back to Panch-bhuta-s.
But Atma is not perishable, but goes back to the Paramatma.
And this awareness / knowledge is 'Jnanam' ( Atmeeyam).
Next : Slokam-4.
To be continued .....