(सर्वासामुपासनानां गतेः फलस्य च विधायकं ब्राह्मणम् ) यदा वै पुरुषोऽस्माल्लोकात्प्रैति स वायुमागच्छति ।तस्मै स तत्र विजिहीते यथा रथचक्रस्य खम् ।तेन स ऊर्ध्व आक्रमते ।स आदित्यमागच्छति ।तस्मै स तत्र विजिहीते ।यथा लम्बरस्य खम् ।तेन स ऊर्ध्व आक्रमते ।स चन्द्रमसमागच्छति ।तस्मै स तत्र विजिहीते ।यथा दुन्दुभेः खम् ।तेन स ऊर्ध्व आक्रमते ।स लोकमागच्छत्यशोकमहिमम् ।तस्मिन् वसति शाश्वतीः समाः ॥बृह. ५,१०.१ ॥
In plain words
When a man departs from this world, he comes to the wind; and there it makes an opening for him as wide as the hole of a chariot wheel, and through it he mounts upward. He comes to the sun, and there it makes an opening for him as wide as the hole of a drum, and through it he mounts upward. He comes to the moon, and there it makes an opening for him as wide as the hole of a kettledrum, and through it he mounts upward. He comes to a world without sorrow and without cold, and there he dwells for everlasting years.
The commentators
Bṛhadāraṇyakopaniṣadbhāṣyam· Leaf 10.45· bhāṣya
सर्वेषामस्मिन्प्रकरणे उपासनानां गतिरियं फलं चो- च्यते— यदा वै पुरुषः विद्वान् अस्मात् लोकात् प्रैति श- रीरं परित्यजति, सः तदा वायुम् आगच्छति, अन्तरिक्षे तिर्यग्भूतो वायुः स्तिमितः अभेद्यस्तिष्ठति ; स वायुः तत्र
In plain words
For every meditation taught in this whole section, this is the one shared destination and reward now being described. 'When a person who truly knows departs from this world' simply means he lets go of the body. He comes first to Air, stretched motionless across the space between earth and sky, standing there impossible to break through. That very Air, there—
Close to the Sanskrit
For all the meditations set forth in this section, this same destiny and fruit is now declared: 'when, indeed, a person who is a knower departs from this world' means he abandons the body. He then comes to Vāyu; in the intermediate space, spread crosswise, Vāyu stands still, impenetrable. That Vāyu, there—
Bṛhadāraṇyakopaniṣadbhāṣyam· Leaf 10.46· bhāṣya
स्वात्मनि तस्मै संप्राप्ताय विजिहीते स्वात्मावयवान् विगम- यति छिद्रीकरोत्यात्मानमित्यर्थः । किंपरिमाणं छिद्रमित्यु- च्यते— यथा रथचक्रस्य खं छिद्रं प्रसिद्धपरिमाणम् ; तेन छिद्रेण स विद्वान् ऊर्ध्वः आक्रमते ऊर्ध्वः सन् गच्छति । स आदित्यमागच्छति ; आदित्यः ब्रह्मलोकं जिगमिषोर्मा- र्गनिरोधं कृत्वा स्थितः ; सोऽपि एवंविदे उपासकाय द्वारं प्रयच्छति ; तस्मै स तत्र विजिहीते ; यथा लम्बरस्य खं वादित्रविशेषस्य छिद्रपरिमाणम् , तेन स ऊर्ध्व आक्र- मते । स चन्द्रमसम् आगच्छति ; सोऽपि तस्मै तत्र विजि- हीते ; यथा दुन्दुभेः खं प्रसिद्धम् ; तेन स ऊर्ध्व आक्रमते । स लोकं प्रजापतिलोकम् आगच्छति ; किंविशिष्टम् ? अ- शोकं मानसेन दुःखेन विवर्जितमित्येतत् ; अहिमं हिमव- र्जितं शारीरदुःखवर्जितमित्यर्थः ; तं प्राप्य तस्मिन् वसति शाश्वतीः नित्याः समाः संवत्सरानित्यर्थः ; ब्रह्मणो बहून्क- ल्पान् वसतीत्येतत् ॥
In plain words
Air opens up there, in its own being, once the traveler arrives — which simply means it parts its own substance and makes itself passable, like a hole opening in something solid. How large is that opening? Just the familiar size of a chariot wheel's hub. Through it, the one who truly knows climbs upward, rising as he goes. He reaches the sun — and the sun, which normally blocks the path of anyone trying to reach Brahmā's world, makes an exception here: for someone who has meditated and knows this way, it opens a door, a passage sized like the hollow of a lambara drum, and through it he climbs higher. He reaches the moon, and the moon opens for him too, this time like the hollow of a great kettle-drum, and through it he rises further still. At last he reaches the world of Prajāpati itself. What marks that world out? It is free of grief — no mental suffering reaches there — and free of cold, meaning free of every bodily pain as well. Once he arrives, he lives there for years the text calls 'everlasting' — which is to say, for kalpa after kalpa of Brahmā's own vast lifetime.
Close to the Sanskrit
In its own self, for him having arrived, it opens up — [meaning] it disperses the parts of its own being, renders itself perforated; that is the meaning. What is the size of this opening? It is asked: like the hole of a chariot-wheel, a well-known size. Through that opening, that knower ascends, going while ascending. He comes to the sun; the sun, having blocked the path of one wishing to go to the world of Brahman, stands so; that one too, for one who thus knows, the worshipper, grants a door; for him, that one opens up there; like the hole of a lambara, a particular instrument, is the size of its opening; through that he ascends. He comes to the moon; that one too, for him, there, opens up; like the hole of a kettle-drum, a well-known size; through that he ascends. He comes to a world, the world of Prajāpati. Distinguished by what? Griefless — devoid of mental suffering, that is this; free from cold — devoid of cold, that is, devoid of bodily suffering; that is the meaning. Having attained that, he dwells there for 'everlasting years' — meaning perpetual years, that is, years; that is the meaning — meaning he dwells for many kalpas of Brahmā; that is this.