यज्ज्ञानात्सर्वविज्ञानं श्रुतिषु प्रतिपादितम् ।मृदाद्यनेकदृष्टान्तैस्तद्ब्रह्मेत्यवधारय ॥ ३२ ॥
In plain words
Know one thing and you know everything — the Upaniṣads say so plainly, and they say it over and over with clay and a dozen other examples. That one thing is Brahman. Settle it.
Close to the Sanskrit
That from the knowledge of which the knowledge of all is expounded in the Upaniṣads, by many illustrations beginning with clay — ascertain that as Brahman.