Kaṭha Upaniṣad · 2.2.1

पुरमेकादशद्वारमजस्यावक्रचेतसः । अनुष्ठाय न शोचति विमुक्तश्च विमुच्यते । एतद्वैतत् ॥ १ ॥

puram ekādaśadvāram ajasyāvakracetasaḥ | anuṣṭhāya na śocati vimuktaś ca vimucyate | etad vai tat || 1 ||

The city of eleven gates of the unborn of straight mind — having meditated on it, he does not grieve; liberated, he is liberated. This is in truth That.

This verse initiates Valli 2.2 with the famous metaphor of the body as a city.

Puram ekādaśadvāram — the city of eleven gates. The body with its ten apertures (eyes, ears, nose, mouth, etc.) plus the mind.

Ajasya — of the unborn. The Ātman that neither is born nor dies.

Avakracetasaḥ — of straight mind. Without deviations, without perversities.

Anuṣṭhāya na śocati — having meditated, he does not grieve. Constant practice liberates from suffering.

Vimuktaḥ ca vimucyate — liberated, he is liberated. Liberation of what is already free.

Etad vai tat — this is in truth That.

In yoga, consciousness of the body as the “city” of the Ātman cultivates detachment and introspection.