The works of Ādi Śaṅkarācārya

Bṛhadāraṇyakopaniṣadbhāṣyam

Verse 225

यद्वै तन्न जिघ्रति जिघ्रन्वै तन्न जिघ्रति न हि घ्रातुर्घ्रातेर्विपरिलोपो विद्यतेऽविनाशित्वात्र तु तद्वितीयमस्ति ततोऽन्यद्विभक्तं यज्जिघ्रेत् ॥ २४ ॥

In plain words

When he seems not to smell anything in that state, he is still smelling—the power to smell is simply what he is, and it can never be lost, because it can never die. There is no second thing left out there, apart from him, for him to smell.

Close to the Sanskrit

That which he does not smell there—smelling, indeed, he does not smell there; for there is no loss of the smeller's smelling, because it is imperishable. But there is not a second thing, other than that, separate, which he could smell.