The works of Ādi Śaṅkarācārya

Chāndogyopaniṣadbhāṣyam

Verse 325

सोऽहं भगवो मन्त्रविदेवास्मि नात्म-

In plain words

I, O venerable sir, am indeed a knower of sacred texts, but I am not a knower of the Self—

Close to the Sanskrit

That I, O venerable one, am indeed a knower of mantras, not of the self—