Veda means knowledge, and one of the categories of knowledge in the Vedas is Vedānta, which means the conclusion of knowledge. Such a conclusion must be complete and consistent.
The thousands of books of the Vedas are summarized in extremely terse form in the Vedānta-sūtras, and the Vedānta-sūtras are explained in the Śrīmad-Bhāgavatam. Śrīmad-Bhāgavatam describes itself as the literary incarnation of God, not as a part of the universe. The words and texts texts have definite forms represented in the world, but the knowledge they represent is full and absolute.
Multiple books of the Vedas say Brahmā heard the seed verses of the Vedas after he awoke in a world of nothingness, and these sounds taught him how to create the objects of the universe.
The Vedas are traditionally known as apauruṣeya, which means having no human author. Here is an example of a verse from Śrīmad-Bhāgavatam claiming to be of Divine origin, albeit with a somewhat awkward translation from Sanskrit:
SB 11.21.38-40: Just as a spider brings forth from its heart its web and emits it through its mouth, the Supreme Personality of Godhead manifests Himself as the reverberating primeval vital air, comprising all sacred Vedic meters and full of transcendental pleasure. Thus the Lord, from the ethereal sky of His heart, creates the great and limitless Vedic sound by the agency of His mind, which conceives of variegated sounds such as the sparśas. The Vedic sound branches out in thousands of directions, adorned with the different letters expanded from the syllable oṁ: the consonants, vowels, sibilants and semivowels. The Veda is then elaborated by many verbal varieties, expressed in different meters, each having four more syllables than the previous one. Ultimately the Lord again withdraws His manifestation of Vedic sound within Himself.
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