From the Brahmanas and especially while in the Upanishads, philosophical texts that increase a contemplative dimension for the Vedic texts, The easy syllable Cundī dhāraṇī or mantra also first appeared in the Kāraṇḍavyūhasūtra: namaḥ saptānāṃ samyaksaṃbuddha koṭīnāṃ tadyathā oṃ cale cule cunde svāhā Classical mantras are thought of sacred syllables https://www.instagram.com/tantramantraaurvigyaan/