Srimad Bhagavad-Gita :
Chapter-13. ( Kshetra-kshetrajna-vibhaga-yogam )
Slokam-1. ( Arjuna question to Lord Sri Krishna ) -
(Arjuna said: O Lord, I wish to know about prakrti [nature], Purusha [the experiencer], and the field and the knower of the field, and of knowledge and the end of knowledge. )
prakrtim purusham caiva kshetram kshetragjnameva ca,
etadveditumicchami jnanam jneyam ca kesava.
arjuna uvaca = Arjuna said;
kesava! = O Lord;
prakrtim purusham ca eva = nature, and the experiencer;
kshetram kshetragjnam ca eva = kshetram (body), and kshetragjnan ( jivatma );
jnanam jneyam ca etat = jnanam ( knowledge ), jneyam ( object of the knowledge, all about these;
veditum icchami = I wish to know.
Just as a well planted field yields abundant results and a poorly planted field yields poor results.
One who has realised that the atma is not the same and different from the ksetra is factually a ksetra-jna one who is a knower of truth.
This is the conclusion of knowledgeable persons well versed in the spiritual truths of the Vedic scriptures.
Although ordinary beings are under the misconception that they are the physical body, believing themselves to be male or female, young or old etc., and convinced that when their physical body feels happiness they are joyful and when their physical body feels unhappiness they are sad.
The word sariram meaning the physical body denotes etymologically as that which decays.
Still there are many in this world that are competent to discriminate between the two and this Lord Krishna emphasises with the words tat-vidah meaning persons endowed with knowledge of the absolute truth.
So the conclusion is that although ordinary beings who are steeped in ignorance do not have the qualification to discriminate between the external physical body and the internal atma; the devotees of Lord Krishna have qualified themselves by hearing from the bonafide spiritual master and studying the Vedic scriptures are able to discriminate between the ksetra and the atma.
To be continued ....