In the earlier sloka we have seen that lord Krishna brings out the illusionary nature of the world. After explaining the illusionary nature , he says that one can come out of this maya or illusion only by cutting down this tree of illusion with the weapon of detachment born out of viveka or discrimination.
In the 4th sloka Lord Krishna explains the nature of the Ultimate reality, the goal of our life. He explains what a person achieves once he cuts down the tree of the world or realizes the world as an illusion.
15.4 – Tatah padam tat parimargitavyam yasmin gata na nivartanti bhuyaat
Tameeya chadyam purusham prapadhyee yathah pravrittihi prasritha purani
Meaning of words:
Tatah – after that(after cutting the tree )
Padam – the goal ( ultimate reality)
Tat – that
Parimaargitavyam – realized or sought after..
Yasmin – where ,into which state
Gata – after going
Na nivartanti – will not return
Bhuyaat – into the world
Tameeya --- that
Chadyam – has existence from the beginning
Purusham – the ultimate reality / the supreme being
Prapadhyee – I take refuge
Yathah – from whom
Pravrithi --- manifestation of the world/creation
Prasriitha – has ensued from
Purani – the eternal
Meaning of sloka
After cutting the tree of the world , a person realizing the ultimate truth. He reaches an ultimate state reaching which there is no return back to the world.
I take refuge in this Ultimate reality or brahmam, which is the cause of the world.
Here Cutting the tree means gaining knowledge that the world is an illusion. Lord Krishna explains here that a person should understand that the whole world is an illusion and its substratum being the Utlimate reality of the Brahman or sat chit Ananda. Once he comes out of the illusion of the world. He realizes the self of the nature of sat chit Anada. Once he dwells in the self , he never returns back to the world. Unless a person comes out of the world, he wouldn’t understand the substratum of the world, as a person who in the woods cannot get the entire picture of the woods, until he comes out of it.
Meaning even though the person stays in this world, does activities in this world, he ever remains in the self. He will be unaffected by the fruits of his actions , nor expects any results of the actions he does. He is ever unaffected by the world. Thus he is in the self all the time and doesn’t return to the world. Such a person is a realized self.
This ultimate reality of brahmam is the cause of the whole world . The world exists due to brahmam or consciousness. Remove the consciousness and the world is gone. But without the world consciouness exists. Hence the source of the world, the root cause of the world is brahmam or consciousness, which is but the nature of the self.