Hindu scripture is overwhelmingly written in Sanskrit. Indeed, much of the morphology and linguistic philosophy inherent in the learning of Sanskrit is inextricably linked to study of the Vedas and relevant Hindu texts. Hindu texts are typically seen to revolve around many levels of reading, namely gross/physical, subtle and supramental. This allows for many levels of understanding as well, implying that the truth of the texts can only be realized with the spiritual advancement of the reader. It is divided into two categories: Shruti- that which is heard (I.e. revelation) and Smriti- that which is remembered (I.e. tradition, not revelation).
The Vedas are considered scripture by all Hindus. While the overwhelming majority of Hindus may never read the Vedas, the reverence for the more abstract notion of eternal knowledge (Veda means knowledge) is etched deep into the hearts of all those who follow Veda Dharma. Classed with the Vedas (which specifically refer to the Rig, Yajur, Sama and Atharva) are their famous commentaries, the Upanishads. While the early Vedas lay the foundation for subsequent Hindu ritual, cosmology and developing philosophy, the Upanishads built the edifice of mystic insight and abhorrence for ritual at the expense of spiritual insight. Forming the core of the Vedanta (End of Vedas), they streamline the excessive litany of praise to Vedic gods and capture the essence of the Rig Vedic dictum "Truth Is One." They set Hindu philosophy apart with its embrace of a single transcendent and yet immanent force that is native to each man's soul, an identification of micro- and macrocosm as One. It can be said that while early Hinduism is most reliant on the four Vedas, Classical Hinduism, from the Yoga and Vedanta to Tantra and Bhakti streams, was molded around the Upanishads.
The Bhagavad Gita occupies a special position in the hearts of most Hindus as a keystone yoga upanishad whose eternal words perhaps are the most representative of all Hindu thought, each shloka 'directly' from the mouth of the Lord Krishna. While technically it is considered Smriti, it has singularly achieved nearly unquestioned status as Shruti, or revealed, and is thus the most definitive single Hindu text, read by millions of bhaktas (devotees) and yogis on a largely daily basis throughout the Sanatana Dharmic world. See Bhagavad Gita to explore this text.
The post-Vedic Hindu scriptures form the latter category, the most notable of which are the Mahabharata and the Ramayana, major epics considered scripture by most followers of Sanatana Dharma, their stories arguably familiar to the vast majoriy of Hindus living in the Indian subcontinent, if not abroad. Other texts considered important by today's Hindus include the Devi Mahatmya, an ode to Devi, the Divine Mother, and the Yoga Sutras, a key meditative yoga text of Shri Patanjali. There are also a number of revered Hindu Tantras and Sutras that command the respect of various Hindu sects of different persuasion, some including the Mahanirvana Tantra, Tirumantiram and Shiva Sutras.
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