In plain words
‘Manomūlam idaṃ jagat.’ This mind pervades the whole universe. For the mind there is no destruction. Taking such a body as the support, every person must strive for the state in which the principle of the mind is brought into experience. There is no place where the mind is not. The very form of this mind turns into the form of Brahman. Students who recognise such oneness must spread through the world today.
The Divinity that pervades the whole universe is attained only through experience
Uddālaka tried to teach his one and only son, Naciketa, many kinds of knowledge of the Ātma. There was no other scholar greater than Uddālaka. Though he was so excellent a scholar, he sent his son to another guru to pursue his studies. The reason is that a son does not trust his father as a guru. He trusts him as a father. As long as the feeling of a father is there, the place of a guru does not come to him. That is why he sent Naciketa to another guru, so that the feeling of a father would be set aside and the feeling of a guru developed. Uddālaka recognised in Naciketa some of the weaknesses that are in these students. Through the guru he heard the teaching that the principle of Brahman is all-pervading. When he came home, he said, ‘Father! I have recognised the principle of Brahman.’ ‘What did you recognise it as?’ asked the father. The son answered that he had recognised it as ‘Brahman is all-pervading’.
Does valour come the moment one grips a sword? Does one become master of the notes the moment one takes a vīṇā in hand?
‘Foolish fellow! It is not enough to learn in words the truth that God is all-pervading,’ remarked Uddālaka. Today this is the student's weakness. What is learnt is an atom's worth; what is talked of is endless. Uddālaka rebuked Naciketa, saying that such a thing is of no use. ‘Bring some water in a small vessel,’ he said. He brought it and set it down before his father. Then he said, ‘Go inside, ask your mother and bring some sugar!’ He brought the sugar and gave it to him.