तद्व्यक्षरत्तदादित्यमभितोऽश्रयत्तद्वा एतद्यदेतदादित्यस्य मध्ये क्षोभत इव ॥ ३.५.३ ॥
In plain words
It flowed forth and settled about the sun; and that is what seems to quiver in the middle of the sun.
The commentators
Chāndogyopaniṣadbhāṣyam· bhāṣya
अथ येऽस्योर्ध्वा रश्मय इत्यादि पूर्ववत् । गुह्या गोप्या रहस्या एव आदेशा लोकद्वारीयादिविधय उपासनानि च कर्माङ्गविषयाणि मधुकृत , ब्रह्मैव शब्दाधिकारात्प्रणवाख्य पुष्पम् । समानमन्यत् । मधु एतत् आदित्यस्य मध्ये क्षोभत इव समाहितदृष्टेर्दृश्यते सचलतीव ॥
In plain words
Now, those upward rays of the sun and so forth are as explained before. Secret, guarded, and esoteric instructions, methods for opening the doors of worlds, meditations, and subsidiary ritual practices form the honey-makers; and Brahman itself, by authority of the scriptural text, is the flower called Praṇava. The rest is similar. This honey of the sun is seen right in the center by a focused observer, appearing as though it is churning and trembling with life.
Close to the Sanskrit
Now, which are his upward rays and so forth, as before. Hidden, guarded, and secret injunctions, methods concerning world-doors, meditations, and subjects related to ritual limbs, the honey-makers; Brahman indeed, because of the governance of the word, is the flower named Praṇava. The rest is similar. This honey of the sun is seen in the middle as if agitating by one whose vision is concentrated, as if moving.