When the five organs of perception become still, together with the mind, and the intellect ceases to be active: that is called the Supreme State [Brahma-Vidya or Self Knowledge]

~Katha Upanishad 2.3.10

Shankara’s commentary on this above verse (Katha Upanishad, verse 2.3.10) states the following:

‘At the time when the five senses…, together with the mind…, which is now no longer functioning and thinking, are at rest in the Self alone, after turning away from objects, and with the intellect…no longer engaging with its functioning, that they call the highest state [Brahma-Vidya or Self-Knowledge].’

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