Cundī dhāraṇī or mantra also 1st appeared during the Kāraṇḍavyūhasūtra: namaḥ saptānāṃ samyaksaṃbuddha koṭīnāṃ tadyathā oṃ cale cule cunde svāhā The usage of mantra or even the repetition of selected phrases in Pali is really a very frequent type of meditation in the Theravada tradition. Very simple mantras use repetition https://www.youtube.com/@Mahavidyabaglamukhi/