Aṇḍāntara-stha-paramāṇu-cayāntara-stham (Bs. 5.35). This ātmā and Paramātmā, kṣetra, kṣetrajṣa, is very nicely explained in the Thirteenth Chapter of Bhagavad-gītā. You'll profit by reading that. The Lord says that this body is kṣetra. Kṣetra means the field of activities. Everyone is acting according to the body he has got by the grace of material nature. So the body is the field of activity, and you or me, ātmā, we are the proprietor of the body. We are called kṣetrajṣa. And Kṛṣṇa says, kṣetra-jṣaṁ cāpi māṁ viddhi sarve kṣetreṣu bhārata (BG 13.3).
Now, I am present in my body, you are present in your body, but the Paramātmā, or Supersoul, is present in everyone's body. Another example can be given. Just like this house, there are many apartments. So I am occupying this apartment; another tenant is occupying another apartment. But the landlord is occupier or the proprietor of all the apartments. That is the difference between ātmā and Paramātmā. I am proprietor of the things which has been offered to me by material nature, but God, or Paramātmā, is the proprietor of everything. That is the difference.
Prakṛteḥ kriyamāṇāni guṇaiḥ karmāṇi sarvaśaḥ (BG 3.27). Prakṛti, the material nature, is offering me as I want. She is supplying ingredients. If I want to be human being, then he supplies a similar body, and if I want to become a dog, she supplies similar body.
So actually, we are under the grip of this material nature, and we are being pushed life after life in different bodies by the influence of material nature. Prakṛteḥ kriyamāṇāni guṇaiḥ karmāṇi sarvaśaḥ (BG 3.27). How prakṛti, nature, is working? According to the quality we acquire. Gunaiḥ.
There are three qualities: the good quality, the quality of passion and the quality of ignorance. So we are being contaminated by certain type of quality, and the nature is supplying me a type of body. And there are 8,400,000's of bodies, and we are going through them in a cycle. And as soon as we become, I mean to say, devotee, or we look forward to the Paramātmā, then we can be free from the cycle of repeated birth and death.
This yoga system is . . . meditation means to find out the Paramātmā. The Paramātmā is described in the śāstras: His feature, His body, His hand, Supersoul. And one has to meditate. And by meditation, when one is in samādhi, always thinking of the Supersoul, then he becomes freed from this material entanglement. That is self-realization. That is liberation. So Paramātmā and individual ātmā, or the living creature, they are qualitatively one but quantitatively different.