BG Chap 13 - The Super-knower and knowledge
Kṛṣṇa alone, as the Paramātmā, is the knower of the field in all bodies. The jīvas know their own individual bodies as means of enjoyment and liberation, as citizens know the field they own and cultivate. But the Lord alone (api) knows all the bodies (sarva-kestresu) which must be supported by Him for their very existence. Thus the Lord is the knower of all fields, like a king. Also, the soul can only imperfectly know his own body, whereas the Supersoul has complete and perfect knowledge of all bodies. Thus Kṛṣṇa claims to be absolutely cognizant and the source of all cognition.
Knowledge is to know the field and the two types of knowers of the field. Knowledge is the ability to distinguish between the two knowers of the field – the jīva and the Lord – and relation of these two with the field (prakṛti or the body). To understand both the soul and the Supersoul as one yet distinct is knowledge. One who does not understand the field of activity and the knower of activity is not in perfect knowledge. The living entity’s realization that “I am not this body” constitutes enlightenment. Such enlightenment, however, born of the mode of goodness, is insufficient for liberation. When his knowledge increases to include knowledge of the Supersoul, he becomes liberated. Thus to come to the brahma-bhūta (liberated) platform, one needs to know the Supersoul.
Kṛṣṇa alone is the field as a whole and knower of the field in all bodies. The field and knower of the field are not different from Kṛṣṇa since He pervades everything and everything is dependent on Him for its manifestation and continued existence. Thus Kṛṣṇa considers knowledge as knowing Him to be the field and knower of the field, since He is one with them by maintaining and pervading them both.