एष ह वै यज्ञो योऽयं पवते एष ह यन्निदं सर्वं पुनाति यदेष यन्निदं सर्वं पुनाति तस्मादेष एव यज्ञस्तस्य मनश्च वाक्च वर्तनी ॥ ४.१६.१ ॥
In plain words
This that blows is the sacrifice, for as it goes it purifies all this. And since as it goes it purifies all this, it is the sacrifice. Its two tracks are the mind and speech.
The commentators
Chāndogyopaniṣadbhāṣyam· Leaf 7.61
रहस्यप्रकरणे प्रसङ्गात् आरण्यकत्वसामान्याच्च यज्ञे क्षत उत्पन्ने व्याहृतयः प्रायश्चित्तार्था विधातव्याः, तदभिज्ञस्य च ऋत्विजो ब्रह्मणो मौनमित्यत इदमारभ्यते—
एष वै एष वायुः योऽयं पवते अयं यज्ञः । ह वै इति प्रसिद्धार्थावद्योतकौ निपातौ । वायुप्रतिष्ठो हि यज्ञः प्रसिद्धः श्रुतिषु, ‘स्वाहा वातेधाः’ ‘अयं वै यज्ञो योऽयं पवते’ इत्यादिश्श्रुतिभ्यः । वात एव हि चलनात्मकत्वात्क्रियासमवायी, ‘वात एव यज्ञम्यारम्भको वातः प्रतिष्ठा’ इति च श्रवणात् । एष ह यन् गच्छन् चलनं इदं सर्वं जगत् पुनाति पावयति शोधयति । न हि अचलतः शुद्धिरस्ति । दोषनिरसनं चलतो हि दृष्टं न स्थिरस्य । यत् यस्माच्च यन् एष इदं सर्वं पुनाति, तस्मादेष एव यज्ञः यत्पुनातीति । तस्यास्यैवं विशिष्टस्य यज्ञस्य वाक्च मन्त्रोच्चारणे व्यापृता, मनश्च यथाभूतार्थज्ञाने व्यापृतम्, ते एते वाङ्मनसे वर्तनी मार्गौ, याभ्यां यज्ञस्तायमानः प्रवर्तते ते वर्तनी ; ‘प्राणापानपरिचलनवत्या हि वाचश्चित्तस्य चोत्तरोत्तरक्रमो यद्यज्ञः’ इति हि श्रुत्यन्तरम् । अतो वाङ्मनसाभ्यां
In plain words
In the esoteric section, following the context and the shared forest-text tradition, when a flaw occurs in a sacrifice, the mystical utterances are prescribed as expiation, alongside the silence of the priest who knows this truth. Hence this text begins.
This blowing wind is truly the sacrifice. The particles 'ha' and 'vai' indicate established meanings. That the sacrifice has its foundation in the wind is well known from scriptural passages such as 'Placed in the wind, svāhā' and 'This verily is the sacrifice which purifies.' Because wind alone possesses the nature of movement, it is inherently tied to action; as the scripture hears, 'Wind alone is the starter of the sacrifice, wind is its support.'
Close to the Sanskrit
In the esoteric section, due to context and the commonality of being forest texts, when a flaw has arisen in a sacrifice, the vyāhṛtis are to be prescribed as having the purpose of expiation, and the silence of the officiating priest who knows that—therefore this is commenced.
This verily is this wind, which this purifies, this is the sacrifice. 'ha' and 'vai' are particles indicating well-known meanings. For the sacrifice based on wind is well-known from śrutis, from śrutis such as 'svāhā placed in wind', 'this verily is the sacrifice which this purifies' etc. Because wind alone, being by nature in motion, is connected with action, from the hearing that 'wind alone is the starter of the sacrifice, wind is the support'...
Chāndogyopaniṣadbhāṣyam· Leaf 7.62· bhāṣya
यज्ञो वर्तत इति वाङ्मनसे वर्तनी उच्येते यज्ञस्य ॥
In plain words
Because the sacrifice proceeds in this manner, speech and mind are declared to be its two paths.
Close to the Sanskrit
The sacrifice proceeds, thus speech and mind are spoken of as the two paths of the sacrifice.