The Great Epic of the Bhārata dynasty 7.202.18

Bhāratabhāvadīpa 7.202.18

jñānātmānaṃ jñānasvarūpaṃ jñānagabhyaṃ paravidyāprāpyaṃ jñānaśreṣṭhaṃ cinmātrarūpatvenaiva praśasyatamam | ata eva sudurvidamaviṣayatvāddurjñeyam ||