Mahattam Vrata is a rigorously defined Dharmashastra-sanctioned vow observed on Bhadrapada Shukla Pratipada, focused on atma-shuddhi and ethical renewal. Rooted in Puranic calendars and clarified in works such as Anantadeva’s Smriti Kaustubha, it is anchored to the tithi prevailing at local sunrise. The vidhi emphasizes upavasa according to capacity, panchopachara or shodashopachara puja, sustained japa,…