What is "purvas"

The Fourteen Purvas, translated as ancient or prior knowledge, are a large body of Jain scriptures that was preached by all Tirthankaras (omniscient teachers) of Jainism encompassing the entire gamut of knowledge available in this universe. The persons having the knowledge of purvas were given an exalted status of Shrutakevali or "scripturally omniscient persons". Both the Jain traditions, Svetambara and Digambara hold that all the fourteen purvas have been lost. According to tradition, the Purvas were part of canonical literature and deposited in the third section of Drstivada (the twelfth and last canon). Knowledge of Purvas became fairly vulnerable after Lord Mahaviras nirvana (liberation) on account of effects of famine, such that, eventually only one person— Bhadrabahu Svami had a command over it. In accordance with the prophecy of Mahavira, the knowledge of Purvas died within 1,000 years of his nirvana and eventually, the whole of Drstivada disappeared as well.( Bhagvati Sutra 20.8) However, a detailed table of contents of the Drstivada and the Purvas has survived in the fourth Anga, Samavāyānga and Nandīsūtra. Furthermore, certain portions of Drstivada and Purvas is said to have survived in Satkhandāgama and Kasāyaprabhrta, especially the doctrine of Karma.