quality:correction, linguistic:paraphrasing, linguistic:translation, structural:expansion
Scripture

The main Upanishads, the Bhagavadgītā and the Brahma Sūtras are the foundational scriptures in Vedanta. All traditions of Vedanta give a specific exegesis of these texts, collectively called the Prasthānatrayī, literally, three sources.

All prominent Vedantic teachers, including Shankara, Bhaskara, Ramanuja, Madhva, Nimbarka, and Vallabha wrote commentaries on these three sources. The Brahma Sūtras of Badarayana serve as a bhedabheda -based synthesis of the teachings found in the diverse Upanishads, and while there may have been other similar syntheses in the past, only the Brahma Sūtras have survived to the present day. The Bhagavadgītā, with its syncretism of Samkhya, Yoga, and Upanishadic thought, has also been a significant influence on Vedantic thought.

All Vedāntins agree that scripture (śruti) is the only means of knowing (pramāṇa) regarding spiritual matters (which are beyond perception and inference). This is explained by Rāmānuja as follows:

A theory that rests exclusively on human concepts may at some other time or place be refuted by arguments devised by cleverer people.... The conclusion is that with regard to supernatural matters, Scripture alone is the epistemic authority and that reasoning is to be used only in support of Scripture’.

For specific sub-traditions of Vedanta, other texts may be equally important. For example, for Advaita Vedanta, the works of Adi Shankara are nominally central, though other teachers were equally, or even more, influential. For the theistic Vaishnava schools of Vedanta, the Bhāgavata Purāṇa is particularly important. The Bhāgavata Purāṇa is one of the most widely commented upon works in Vedanta. This text is so central to the Krishna-centered Vedanta schools that the Vedantin theologian Vallabha added the Bhāgavata Purāṇa as a fourth text to the Prasthānatrayī (three classic scriptures of Vedanta).