हंसस्ते पादं वक्तेति स ह श्वोभूते गा अभिप्रस्थापयांचकार ता यत्राभि सायं बभूवुस्तत्राग्निमुपसमाधाय गा उपरुध्य समिधमाधाय पश्चादग्नेः प्राङुपोपविवेश ॥ ४.७.१ ॥
In plain words
"A swan will tell thee a foot." When the next day came, he drove the cows on; and where they were at evening, there he laid a fire, penned the cows, put on fuel, and sat down behind the fire facing east.
The commentators
Chāndogyopaniṣadbhāṣyam· bhāṣya
सोऽग्निः हंसः ते पादं वक्तेत्युक्त्वा उपरराम । हंस आ- दित्यः, शौक्ल्यात्पतनसामान्याच्च । स ह श्वोभूते इत्यादि समानम् ॥
In plain words
That fire said, 'The Haṃsa will teach you this quarter,' and then fell silent. The Haṃsa is the sun, by reason of its brightness and its motion through the sky. The rest of the narrative on the following morning proceeds just as before.
Close to the Sanskrit
That fire said, 'The Haṃsa will speak to you the foot,' having spoken thus, it ceased. Haṃsa is the sun, because of whiteness and because of the commonality of motion. That indeed on the morrow, and so forth, is equal.