BG 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 become accomplished in the practice of devotional service enjoys this knowledge within himself in due course of time.

4.38. In this world there exists no purifier comparabel to knowledge. One who becomes perfect in Yoga finds this, on his own accord, in his Self in course of time.

4.38 There is nothing in the world so purifying as wisdom; and he who is a perfect saint finds that at last in his own Self.

4.38 Na hi etc. There exists no purifier similar to the knowledge. The purity of other things is due to the touch of Consciousness and is not intrinsic. This point is not elaborated here for fear of a lengthy discussion. This purifying nature of the knowledge, one would understand for himself on reaching the stage of being perfectly enlightened.

4.38 Nothing here in this world purifies like this knowledge; for the knowledge of the self destroys all evil. He who has reached perfection by practising Karma Yoga in its form of knowledge daily in the manner taught, in due time, of his own accord, attaints it, i.e., knowledge concerning his own self. Sri Krsna expounds the same lucidly thus:

4.38 Hi, indeed; na vidyate, there is nothing; pavitram, purifying, sanctifying; iha, here; sadrsam, comparable; jnanena, to Knowledge. Yoga-samsiddhah, one who has become perfected, who as attained fitness through yoga-the seeker after Liberation who has become samsiddhah, purified, qualified; yogena, through the yoga of Karma and the yoga of concentration-; kalena, after a long time; vindati, realizes, i.e. attains; tat, That, Knowledge; verily svayam, by himself; atmani, in his own heart. That means by which Knowledge is invariably attained is being taught:

4.38 For there is no purifier here eal to knowledge; he that is perfected in Karma Yoga finds this (knowledge) of his own accord in himself in due time.

4.38 Indeed, there is nothing purifying here comparable to Knowledge. One who has become perfected after a (long) time through yoga, realizes That by himself in his own heart.