Everyone cannot live in a first-class apartment, because he cannot pay. Similarly, this body is also like apartment. According to your capacity of paying the rent or the price you get a certain type of . . . Kāraṇaṁ guṇa-saṅgo 'sya sad-asad-janma-yonisu (BG 13.22). This is going on. We are not this apartment; we are the occupier of the apartment. That is real knowledge. There are two persons: one is the occupier and one is the proprietor. We have got practical knowledge.
So Kṛṣṇa says clearly that,
- kṣetra-jñaṁ cāpi māṁ viddhi
- sarva-kṣetreṣu bhārata
- kṣetra-kṣetrajñayor jñānaṁ
- idaṁ śarīraṁ kṣetram ity abhidhīyate
- (BG 13.3)
In the Bhagavad-gītā you'll find this knowledge, kṣetra-kṣetrajñaḥ. Kṛṣṇa says that "This body is called kṣetra." Arjuna inquired from Kṛṣṇa, "What is kṣetra, what is kṣetrajñaḥ, what is jñāna, and what is subject matter of jñāna?" So Kṛṣṇa answered that kṣetra means this body, and kṣetrajñaḥ means one who knows that "This is my body." He is kṣetrajñaḥ. You study your own body. You study your finger. You'll never say "I finger"; "My finger." Nobody says. Even a small child, you ask him, "What is this?" He'll say "My finger." He'll never say "I finger." I am not finger. I'm not this. So one who knows that this body is mine, that is kṣetra, ah, kṣetrajñaḥ. And the body is kṣetra. Ksetra means the field of activities.