स्वयमेवात्मनाऽत्मानं वेत्थ त्वं पुरुषोत्तम।भूतभावन भूतेश देवदेव जगत्पते॥
swayam evātmanātmānaṃ vettha tvaṃ puruṣottamabhūta-bhāvana bhūteśa deva-deva jagat-pate
Word by word
The verse says
You alone know yourself, by yourself, highest person — you who bring beings into being, lord of beings, god of gods, lord of the world.
In plain words
Svayam evātmanātmānaṃ vettha — you yourself, by yourself, know yourself.
Three words for self in one line, piled up deliberately.
Arjuna has just said nobody else knows. Here he says who does, and the answer closes the circle.
Where you've felt this · in health
Nobody can tell you how tired you are. Your doctor can measure things, your family can say you look rough, and none of that reaches the actual fact of it. You are the only one inside the only body that knows, and there is no second opinion available on that particular question.
Going deeper
Self-knowledge of this kind is not an achievement, and that is the point of the piled-up words.
In ordinary cases, knowing yourself means looking inward and reporting — which already splits you into an observer and a thing observed. The line here refuses that split. By yourself, of yourself, you know yourself. There is no gap for a method to sit in.
That is also why nobody else can get there. It is not that the information is restricted. It is that the only position from which this is knowable is the one he occupies, and positions are not transferable.
For a reader the honest implication is slightly deflating and also freeing. There is a form of knowing about God that is permanently closed to investigation, however diligent. What the rest of the book offers instead is not a cleverer investigation. It is a relationship, which is available on completely different terms.