In plain words
In what learning have you become expert?’ So he questioned him in many ways. Then Nārada: ‘I have read the four Vedas. I have learned the six śāstras that are the limbs of the Veda,’ he answered Sanatkumāra. Sanatkumāra, smiling: “To know the four Vedas and the six śāstras is a very happy thing indeed. But do you know yourself? Nārada!” he asked. Without knowing yourself, there is no use in merely stuffing so many śāstras, so many Vedas, so many Upaniṣads, so many kinds of Gītās into that head of yours. The moment one knows oneself, all learning comes into one's hands. One then experiences a state beyond all knowledge. ‘Advaita darśanaṃ jñānaṃ’: on whatever day you let go of such duality, on that very day Jñāna will come to you; so Sanatkumāra set out to tell him about himself.
Today the whole world, without knowing itself, claims to have achieved great things of many kinds, and on the strength of the advance of this science sets foot in needless undertakings. When they declare, ‘We are travelling in the sky, we are journeying to the stars, we spend our whole life happily on the moon,’ their greatness simply flies away like castles in the air; the scientists are sinking in a foolishness that cannot understand peace of mind or their own divine principle. So Vēmana said it in small words.
Be it the world of Indra or the world of the moon, you can see it well from Nandi; climb up on Nandi and look with care! Viśvadābhirāma, listen, Vēma.
He said to climb on Nandi and look. By Nandi we understand merely a bull. But here, for the word Nandi, he took the intellect itself to be Nandi. So we push such an intellect away and talk of going off to the moon or the sun; but the Ānanda that comes through our intellect is in the Ātma within us, not in the sky.