Traditionally, A mantra is often a term or sound recurring to assist with concentration in the course of meditation, at first observed in Hindu and Buddhist traditions. This custom was transmitted to Japan by Kūkai (774–835), who Established the Japanese Shingon (Japanese for Zhēnyán) mantra vehicle. Kūkai saw a mantra https://www.youtube.com/watch?v=7yoEpl90KUg