Śāstram — The Complete Body of Sacred Authority
Śāstram (from the root śās, to command, to instruct, to rule; 'authoritative teaching') denotes any body of knowledge that functions as a regulative authority — sacred law, sacred science, or revealed teaching. In Śrī Vaiṣṇava usage, the term encompasses the entire field of divinely authoritative texts: the four Vedas with their ancillary literature (Vedāṅgas), the Upaniṣads, the Brahma Sūtras, the Bhagavad Gītā, the two great Itihāsas (Rāmāyaṇa and Mahābhārata), the Mahā Purāṇas (especially Viṣṇu Purāṇa and Bhāgavata Purāṇa), the Pañcarātra Āgamas, and crucially, the Nālāyira Divya Prabandham — the four thousand Tamil pāsurams of the twelve Āzhvārs, honored as the Dramiḍopaniṣad (the Tamil Upaniṣad), and the commentarial and original works of the Āchāryas from Nāthamuni to Maṇavāḷa Māmunigaḷ.
The Supreme Aspiration of Śāstram: A central Śrī Vaiṣṇava hermeneutical principle concerns the tātparya (ultimate purpose) of śāstram. The various texts of śāstram prescribe many different upāyams — karma yoga (ritual action), jñāna yoga (knowledge-cultivation), bhakti yoga (devotional meditation), and diverse specific observances. These are not the śāstram's supreme aspiration; they are accommodations for aspirants at different stages of maturity. The ācāryas declare that the supreme aspiration of all śāstram is prapatti — the immediate, total surrender of the soul to Bhagavān through an ācārya. Every other upāyam, rightly understood, points toward and leads to prapatti.
Śāstram and the Ācārya: The Śrī Vaiṣṇava understanding is that śāstram alone, without the living transmission of an ācārya, is insufficient. The same text can yield radically different — and sometimes opposite — readings depending on the interpretive tradition in which it is approached. The ācārya-maṭha (the lineage of teachers) is therefore itself part of the śāstram in its living form. Piḷḷai Lōkācāryar and Maṇavāḷa Māmunigaḷ emphasize that the ācārya's word (ācārya-vacana), precisely because it descends from the unbroken paramparā, carries the authority of śāstram for the disciple.
Śāstram as Prasāda: The ācāryas also point to the remarkable fact that śāstram itself — in its fullest form, including the Tamil Divya Prabandham — is a gift of Bhagavān's grace. The Āzhvārs received their knowledge not through systematic study but through direct divine illumination (mayyaṭinta jñānam). The śāstram they gave the world is therefore not merely human scholarship but Bhagavān's own self-disclosure. This makes engagement with śāstram not a scholarly exercise but an act of receiving the Lord's grace.