Mbh 6.37.2a

“The Holy One said, ‘This body, O son of Kunti, is called Kshetra. Him who knoweth it, the learned call Kshetrajna.[260] Know me, O Bharata, to be Kshetras. The knowledge of Kshetra and Kshetrajna I regard to be (true) knowledge. What that Kshetra (is), and what (it is) like, and what changes it undergoes, and whence (it comes), what is he (viz., Kshetrajna), and what his powers are, hear from me in brief. All this hath in many ways been sung separately, by Rishis in various verses, in well-settled texts fraught with reason and giving indications of Brahman. The great elements, egoism, intellect, the unmanifest (viz., Prakriti), also the ten senses, the one (manas), the five objects of sense, desire, aversion, pleasure, pain, body consciousness, courage,--all this in brief hath been declared to be Kshetra in its modified form. Absence of vanity, absence of ostentation, abstention from injury, forgiveness, uprightness, devotion to preceptor, purity, constancy, self-restraint, indifference to objects of sense, absence of egoism, perception of the misery and evil of birth, death, decrepitude and disease,[261] freedom from attachment, absence of sympathy for son, wife, home, and the rest, and constant equanimity of heart on attainment of good and evil, unswerving devotion to me without meditation on anything else, frequenting of lonely places, distaste for concourse of men,[262] constancy in the knowledge of the relation of the individual self to the supreme, perception of the object of the knowledge of truth,--all this is called Knowledge; all that which is contrary to this is Ignorance.[263] That which is the object of knowledge I will (now) declare (to thee), knowing which one obtaineth immortality.