In plain words
Subtle within the subtle atom, great within the great object, shining everywhere as the witness of all: the Ātma itself is Brahman, Brahman itself is the Ātma.
That which, once known, makes all things known, that without knowing which nothing whatever is known: knowing that which they call the higher and the lower learning, the one who teaches it, he alone is the Sadguru.
All the sacred dharma and karma of Bhārata are ordained by the Veda. The Veda is apauruṣeya. We can only say it is purely the very form of God's Word. But precisely because understanding so unfathomable, so infinite a Veda is impossible for ordinary people, the great ones divided it into smṛti and into purāṇas and itihāsas; working without rest, with single-minded dedication, with unceasing yearning, with endless hope, with an anguish beyond understanding, they turned this śruti they had earned, this śruti they had heard, into a sacred smṛti, turned it into purāṇa, turned it into itihāsa, and handed it to ordinary people in a form fit for them to experience by a natural path. The Vedas were neither written by someone, nor did someone speak them and have them set down in writing in the proper way. This is the sacred śruti that has come down from time without beginning as a line of guru and disciple. That is, it is what the maharṣis heard, solely in the times when they stood most steadfast in their discipline; because hearing is its cause, it has the name śruti as well. No one whatever can change the sacred Vedas. The itihāsas and purāṇas can be commented on in many ways. Many learned people, all of them, may garble them a little.