The works of Ādi Śaṅkarācārya

Sanatsujātīyam

p. 210

p. 210

ज्ञानस्वरूपमत्यन्तनिर्मलं परमार्थतः ।

In plain words

In ultimate truth, it is knowing itself — and utterly without stain.

Close to the Sanskrit

Of the very nature of knowledge, utterly stainless, in the ultimate sense.