In Sanskrit literature, works on astronomy, astrology, and mathematics were all part of the specialised branch of learning known as jyotisssstra or “the science of heavenly bodies”. By the 5th century ce, astronomers had developed the medieval siddhanta genre as a standard textual tradition and organized astronomical schools based on the authority of different authors and their works. The Ganitatilaka is a Sanskrit mathematical text written by sripati, an astronomer-mathematician who hailed from 11th-century ce Maharashtra. “A commentary on the Ganitatilaka was written by Simhatilakasuri Suri, the pupil of Vibudhacandra; this Simhatilakasuri wrote a vrtti on the Bhuvanadipaka of Padmaprabha Suri at Vijapura in 1269”. Simhatilakasuri was an author-monk involved in the codification of a Jain ritual that can be styled as tantric. For the understanding of the development of medieval Jainism, Simhatilakasuri’s Mantrarajarahasya is of special interest; it deals with the surimantra, a Jaina ritualistic formula “from whose power the very continuity of Jainism was regarded as deriving.”