Bhagavad Gita 4.38 Chapter 4, Verse 38

न हि ज्ञानेन सदृशं पवित्रमिह विद्यते ।
तत्स्वयं योगसंसिद्धः कालेनात्मनि विन्दति ॥४.३८॥

na hi jñānena sadṛśaṃ pavitramiha vidyate
tatsvayaṃ yogasaṃsiddhaḥ kālenātmani vindati

Meaning

Truly, nothing in this world purifies like knowledge. One perfected in yoga finds it within oneself in due course.

Newly written by Bhajan Dhun — scholarly review in progress.

Reference: Bhagavad Gita 4.38 (Chapter 4, The Yoga of Knowledge and Renunciation of Action, Verse 38)