Born Shantinath on 27 October 1958 at Sadalga in Belagavi district, Karnataka, he is a younger brother of Acharya Vidyasagar. Remarkably, their parents also took diksha — the father as Muni Mallisagar and the mother as Aryika Samaymati — as did two sisters. Shantinath took a brahmacharya vow in 1975, kshullak diksha at Sonagiri the same year and ailak diksha at Nainagiri in 1978, all from Vidyasagar, and on 8 March 1980 at Dronagiri received muni diksha as Muni Samayasagar.
For over four decades he walked and studied as a muni in his elder brother's sangh, often leading groups of monks on separate vihar. After Acharya Vidyasagar attained samadhi at Chandragiri, Dongargarh, in February 2024, the sangh recognised Samayasagar, its most senior muni by diksha, as successor. On 16 April 2024 he was installed as acharya at Kundalpur in Damoh district, Madhya Pradesh, before a vast gathering. He now leads Vidyasagar's large sangh of munis and aryikas.

