This is the King of sciences, the King of secrets, the supreme Purifier. It is realized by direct perception and is endowed with (great) merit, very easy to perform and of imperishable nature. (Gita Chapter IX verse 2).
This is the King of sciences, the most brilliant of all, the highest, because it is of the greatest benefit to mankind, more beneficial than any other science. Those who are masters in this science know all that there is to be known. All other knowledge is insignificant compared to jnana, the science of the Soul, which brings the highest result. It is for this reason that greater reverence and respect is shown to those who know Brahman, the Truth, than to any other persons of learning. So also it is the King of secrets, the deepest, the most profound of mysteries. Other mysteries may be solved with the help of external means. But this mystery is more profound than any other. To solve it one has to renounce external means; one has to dive deep into one’s own soul. There alone the secret will be revealed. And it is also the greatest of all purifiers. How does it purify? By removing the accumulated results of acts performed during endless incarnations. All our past karma is burned up by this knowledge of Brahman. All our deeds — good, bad and indifferent — committed during thousands of lives are uprooted. No result of them is left. Our debts are paid instantly and we are free.
Moreover this Brahmajnana can be realized. As we realize the feeling of pleasure and pain, so the Truth can become an immediate perception and experience.
Many things are taught in shrutis and smritis, and those can be known through our understanding, by the power of intellect. But this jnana can be experienced. It works a transformation; it is a becoming, a rebirth. Through this knowledge we become new beings. Yes, it is of immense merit, for it teaches about the Atman, how to know ourselves, how to realize our own divine nature.
But if it has all these wonderful qualities, then it must be very difficult to attain. Not so says Bhagavan. It is very easy to acquire. It does not call for difficult practices or severe austerities, as do some other paths. And the greatest of all — it is imperishable. Every other cause is perishable and so too is its effect. But Brahmajnana is eternal and its effect is therefore everlasting. That knowledge of Brahman, of the Atman, results in mukti, or nirvana, which has no end. Therefore, this knowledge is certainly worth acquiring.