The works of Ādi Śaṅkarācārya

Chāndogyopaniṣadbhāṣyam

Bhashya

Bhashya

तेन अक्षरेण उभौ कुरुत , यश्च एतत् अक्षरम् एव यथाव्याख्यात वेद, यश्च कर्ममात्रवित् अक्षरयाथात्म्य न वेद, ता-वुभौ कुरुत कर्म, तयोश्च कर्मसामर्थ्यादेव फल स्यात्, किंतत्राक्षरयाथात्म्यविज्ञानेन इति, दृष्ट हि लोके हरीतकीं भक्षयतो तद्रसाभिज्ञेतरयो विरेचनम्—नैवम्, यस्मात् नानातु विद्या च अविद्या च, भिन्ने हि विद्याविद्ये, तु शब्द

In plain words

An objection might be raised: Both perform the ritual—the one who knows the imperishable as explained, and the one who knows only ritual action without understanding its true essence. Since both perform the act, wouldn't the fruit arise solely from the power of the action itself? What purpose is served by knowing the true nature of the imperishable? Just as the medicinal fruit haritaki produces the same purgative effect whether the person eating it recognizes its taste or not. But this is not so, because knowledge and ignorance are fundamentally different, as indicated by the word 'tu'.

Close to the Sanskrit

By that imperishable both perform: he who knows this imperishable just as explained, and he who is a knower of mere action and does not know the true nature of the imperishable. Both of them perform action, and the fruit would come solely from the power of the action; what use is there of knowing the true nature of the imperishable in that case? For it is seen in the world that the purging effect of the haritaki fruit is identical whether eaten by one who knows its taste or one who does not. It is not so, because knowledge and ignorance are distinct; for knowledge and ignorance are different, and the word 'tu' indicates this.