Veda, Brahmans, and issues of religious authority
For members of the upper castes, a principal characteristic of Hinduism has traditionally been a recognition of the Veda, the most ancient body of Indian religious literature, as an absolute authority revealing fundamental and unassailable truth. The Veda is also regarded as the basis of all the later shastra texts, which stress the religious merits of the Brahmans—including, for example, the medical corpus known as the Ayurveda. Parts of the Veda are quoted in essential Hindu rituals (such as the wedding ceremony), and it is the source of many enduring patterns of Hindu thought, yet its contents are practically unknown to most Hindus. Most Hindus venerate it from a distance. In the past, groups who rejected its authority outright (such as Buddhists and Jains) were regarded by Hindus as heterodox, but now they are often considered to be part of a larger family of common Indic traditions.
Another characteristic of much Hindu thought is its special regard for Brahmans as a priestly class possessing spiritual supremacy by birth. As special manifestations of religious power and as bearers and teachers of the Veda, Brahmans have often been thought to represent an ideal of ritual purity and social prestige. Yet this has also been challenged, either by competing claims to religious authority—especially from kings and other rulers—or by the view that Brahmanhood is a status attained by depth of learning, not birth. Evidence of both these challenges can be found in Vedic literature itself, especially the Upanishads (speculative religious texts that provide commentary on the Vedas), and bhakti literature is full of vignettes in which the small-mindedness of Brahmans is contrasted with true depth of religious experience, as exemplified by poet-saints such as Kabir and Ravidas.