Bhagwad Gita
Chapter 4, Verse 38
न हि ज्ञानेन सदृशं पवित्रमिह विद्यते।
तत्स्वयं योगसंसिद्धः कालेनात्मनि विन्दति।।4.38।।
In this world, there is nothing so sublime and pure as transcendental knowledge. Such knowledge is the mature fruit of all mysticism. And one who has achieved this enjoys the self within himself in due course of time.