Only two kinds of people can attain self-knowledge: those who are not encumbered at all with learning, that is to say, whose minds are not over-crowded with thoughts borrowed from others; and those who, after studying all the scriptures and sciences, have come to realise that they know nothing.
The rishis of old attained the Knowledge of Brahman. One cannot have this so long as there is the slightest trace of worldliness. How hard the rishis laboured ! Early in the morning they would go away from the hermitage, and would spend the whole day in solitude, meditating on Brahman. At night they would return to the hermitage and eat a little fruit or roots. They kept their mind aloof from the objects of sight, hearing, touch, and other things of a worldly nature. Only thus did they realize Brahman as their own inner conciousness.
The truth is that you cannot attain God if you have even a trace of desire. Subtle is the way of dharma. If you are trying to thread a needle, you will not succeed if the thread has even a slight fiber sticking out.
One man may read the Bhagavata by the light of a lamp, and another may commit a forgery by that very light; but the lamp is unaffected. The sun sheds its light on the wicked as well as on the virtuous.
As the shell, the pith and the kernel of the fruit are all produced form one parent seed of the tree, so from the one Lord is produced the whole of creation, animate and inanimate, spiritual and material.
Take the case of the infinite ocean. There is no limit to its water. Suppose a pot is immersed in it: there is water both inside and outside the pot. The jnani sees that both inside and outside there is nothing but Paramatman. Then what is this pot? It is 'I-consciousness'. Because of the pot the water appears to be divided into two parts; because of the pot you seem to perceive an inside and an outside. One feels that way as long as this pot of 'I' exists. When the 'I' disappears, what is remains. That cannot be described in words.