ya evam vetti purusham
prakritim ca gunaih saha
sarvatha vartamano ’pi
na sa bhuyo ’bhijayate
"One who understands this philosophy concerning material nature, the living entity and the interaction of the modes of nature is sure to attain liberation. He will not take birth here again, regardless of his present position."
The Lord tells that he who understands these, even if he [atman] is in a body, and experiencing pleasures and pains, would never have rebirths. Evam = this, purusham = atman, vetti = is understood [of its nature], prakrutim = [and] prakruti [its Five great elements and the body made of them]. Earlier the Lord told the body as Kshetram or cultivable land, and atman which realizes so is Kshetragya. Gunai saha = the Three qualities of satvam, rajas and tamas. That is atman's nature, body's nature and the body associated Three qualities are to be understood. Such a person, sarvatha vartamano'pi = even if residing in a body always, sa = such a person [jeevatman], na bhuya = never again, abhijayate = will have birth. That is he attains atma prapti and is never born again. Understanding atman means, it is superior to body, atomic in size, embodiment of Gyana, embodiment of happiness, experiences happiness in itself, etc. Such a great atman, why should he be bonded inside the body? Because atman desired to experience the pleasures and pains, through the body, which is always associated with satva-rajas-tamas qualities. Thus atman lowers its status. Body is perishable and never permanent, it is composed of the Five great elements; atman resides in a particular body because of past karma; after karma is spent, body is cast off, etc. Atman also realizes the Three qualities always associated with the body. Thus atman, body and the Three qualities are all combined. This combination results in actions and consequent acquisitions of papa/punya, and resulting in rebirths. To come out of this cycle, atman should realize it is in a cycle. Atman is still in this body due to past karma. Even then, once realized the nature of atman, body and the Three qualities, gets liberated after death and is never born again. In spite of being in this World, atman does all necessary to avoid rebirths.