Agni Purana — Mantra-shastra, Shloka 21
The Root-Mantra of Tvaritā
Tvaritā-mūla-mantra
सौम्यादि मध्यमान्तन्तु गुरुत्वं जायते वटे पूर्वादि मध्यमान्तन्तु लघुत्वं कुरुते क्षणात्
saumyādi madhyamāntantu gurutvaṃ jāyate vaṭe pūrvādi madhyamāntantu laghutvaṃ kurute kṣaṇāt
‘सौम्य-’ आदि गण में मध्य और अन्त का अक्षर छन्द में गुरु होता है; पर ‘पूर्व-’ आदि गण में मध्य और अन्त का अक्षर तत्काल लघु हो जाता है।
Lord Agni (teaching chandas/prosody to the inquirer, traditionally Vasiṣṭha)
Vidya Category: {"primary_vidya":"Alamkara","secondary_vidya":"Vyakarana","practical_application":"Chandas-knowledge for composing/reciting verses correctly by applying laghu–guru determination rules to specific gaṇa/word-groups in metrical scanning.","sutra_style":true}
Encyclopedic Reference: {"reference_type":"Definition","entry_title":"Laghu–Guru Niyama for ‘Saumya-’ and ‘Pūrva-’ Groups","lookup_keywords":["chandas","laghu guru","saumya-gaṇa","pūrva-gaṇa","mātrā-vicāra"],"quick_summary":"Defines a prosodic rule: in the ‘saumya-’ class the middle and final syllables are treated as guru, while in the ‘pūrva-’ class the middle and final syllables are treated as laghu, aiding metrical parsing."}
Concept: Śāstra-niyama: knowledge is stabilized by concise operational rules (lakṣaṇa) for correct application.
Application: Use as a mnemonic rule while scanning meters in recitation, composition, and teaching of chandas.
Khanda Section: Chandas & Prosody (Sanskrit Metrics / Pingala-style Laghu-Guru rules)
Primary Rasa: adbhuta
Secondary Rasa: shanta
Visual Art Cues: {"scene_description":"A traditional Sanskrit prosody lesson: a teacher indicates syllable weights (laghu/guru) on a palm-leaf manuscript, marking the middle and final syllables for two named groups.","kerala_mural_prompt":"Kerala mural style, gurukula scene, acharya with palm-leaf manuscript, students seated, red-ochre background, stylized script marks showing laghu and guru, temple-school ambience","tanjore_prompt":"Tanjore painting, ornate frame, acharya teaching chandas, gold highlights on manuscript edges, students with stylus, symbolic laghu-guru marks as decorative motifs","mysore_prompt":"Mysore painting, clean instructional composition, palm-leaf folios with clear laghu/guru notation, calm classroom, fine linework and muted colors","mughal_miniature_prompt":"Mughal miniature, courtly scholar demonstrating prosody, detailed manuscript illumination, precise calligraphy, students observing, architectural interior"}
Audio Atmosphere: {"recitation_mood":"instructional","suggested_raga":null,"pace":"medium","voice_tone":"instructional"}
Sandhi Resolution Notes: मध्यमान्तन्तु = मध्यम-अन्तम् + तु; पूर्वादि = पूर्व-आदि; सौम्यादि = सौम्य-आदि; क्षणात् as ablative singular.
Related Themes: Agni Purana 311 (Chandas/Prosody section)
FAQs
It gives a technical chandas rule: in specified word-classes (“saumyādi” vs “pūrvādi”), the middle and final syllables are to be scanned as guru (heavy) or laghu (light) for metrical counting.
Beyond theology and ritual, the Agni Purana also teaches literary sciences; this verse is part of its prosody toolkit, showing how the text functions as a compact handbook of Sanskrit metrics alongside other disciplines.
Correct metrical recitation preserves the integrity of śloka transmission; maintaining accurate chandas is traditionally held to support proper chanting, learning, and the merit of preserving sacred knowledge.