Sri Aurobindo translates Prashna Upanishad, Sixth Question, Verses 5-8: “Therefore as all these flowing rivers move towards the sea, but when they reach the sea they are lost in it and name and form break away from them and all is called only the sea, so all the sixteen members of the silent witnessing Spirit move towards the Being, and when they have attained the Being they are lost in Him and name and form break away from them and all is called only the Being: then is He without members and immortal. Whereof this is the Scripture: He in whom the members are set as the spokes of a wheel are set in its nave, Him know for the Being who is the goal of knowledge, so shall death pass away from you and his anguish. And Pippalada said to them: ‘Thus far do I know the Most High God: than He there is none Higher.’ And they worshipping him: ‘For thou art our father who hast carried us over to the other side of the Ignorance.’ Salutation to the mighty sages, salutation!”
The image of the rivers losing their separate identities, their names and forms, as they merge with the sea, is one which immediately resonates with all. The recognition that name and form are transient phenomena that are not, in the end, separate from the Divine Existent who creates, constitutes and embodies all, is an important realisation that helps to put the sense of ego into its proper place. The ego is formed for carrying out the individual elements of interaction in the universal manifestation, and it is not separate or distinct from the all-knowing, all-pervading, all-constituting Oneness.
Just as the air inside a jar is the same as the air outside the jar, the water in the river is the same water that is in the sea. The sea water evaporates into the air through the action of the sun. It then forms clouds which drop the water onto the earth in the form of rain, snow, or other forms of liquid precipitation. This then is gathered into rivers which return the water to the sea from whence it arose, to repeat the cycle. At each step of the way, we create a name to define a form, but they are all part of an inseparable unity and are simply phases of the One in manifestation as seen at a moment in Time by our limited mental framework.
When the seeker is able to transcend the limited, fragmented, step-by-step view of the mind and see the creation as One in its entirety and in the various parts that the mind identifies, then he is able to move beyond the mind into the knowledge by identity that carries him beyond Ignorance and Death.
Sri Aurobindo, The Upanishads, Prashna Upanishad, pp.297-315