Muṇḍaka Upaniṣad · 3.2.12
अशरीरं शरीरेष्वनवस्थेष्ववस्थितम् । महान्तं विभुमात्मानं मत्वा धीरो न शोचति
aśarīraṃ śarīreṣv anavastheṣv avasthitam | mahāntaṃ vibhum ātmānaṃ matvā dhīro na śocati
Incorporeal, among bodies that are not his is established; knowing the great, the all-pervading Self, the serene does not grieve.
The Self is not the body, and knowing it frees from suffering.
Aśarīram — incorporeal, formless. The Ātman is not bodily or spatially limited.
Śarīreṣu anavastheṣu — among bodies that are not his. Bodies are instruments, temporary possessions, not identity.
Avasthitam — established, present. Not as owner but as witness, as consciousness.
Mahāntam vibhum — the great, the all-pervading. Without limits, present in everything.
Ātmānam matvā — knowing the Self. Not intellectually but directly realizing.
Dhīraḥ na śocati — the serene does not grieve. Suffering arises from identification with the limited; knowing the unlimited, pain ceases.
Śoka — lamentation, grief, suffering. There is no possible loss for one who knows that the Self never dies.
This is the fruit of yoga: equanimity in the face of all vicissitudes.