Tattvartha Sutra, Uttaradhyayana Sutra and Bhagavati Sutra stating: Bahya Tapas (external austerities): fasting, abstinences, restraint in begging alms, renunciation of delicacies, self-mortification, retreat from the world. Abhyantara Tapas (internal austerities): penance, respect to elders, service to others, study, meditation, abandonment of the body in one's thoughts. In Jainism, Tapas implies a control on desires, and is a form a self purification. Mahavira, the 24th Tirthankara undertook ascetic Tapas for twelve years, after which he attained Kevala Jnana (liberating supreme knowledge). Ajivikas Ajivikas was another ancient Indian religion which survived through about 13th-century CE, but became extinct thereafter, in which Tapas was a central concept as a means of salvation. According to Arthur Basham, the Ajivikas believed in the most rigorous ascetic practices in public. They believed in not harming anything and not being a cause of hurt to any living creature or substance, so they ate refuse, waste products, went deep into forests, mountains or isolated caves to live their austere life. One of the Buddhist canonical texts, Nanguttha Jataka, claims that the Ajivikas perform severe ascetic practices as part of their Tapas, including sleeping on a bed of thorns and other forms of self-mortification. The Jainism text Sthananga Sutra claims that the Ajivikas performed severe penances and self-mortification as part of their Tapas practice. A mention of the ascetic practices of Ajivikas is found in Chinese and Japanese Buddhist literature, where they are spelled as Ashibikas. Ajivikas were a Śramaṇa religion, just like Buddhism and Jainism, and these competed with each other. Most of the Ajivika texts have not survived. The Tapas practices of Ajivikas, as well as other information about them is primarily from the Buddhist and Jain texts; scholars question whether the description of Ajivikas has been fairly and completely summarized in these, or are these polemic misrepresentations. Modern practice Modern practitioners pursue Tapas - meditation and study of religion in ashrams across India. See also Ataptatanu Nirvana, Brahmacharya, Moksha Satyagraha, Gandhism Soma Tapas (Jain religion) Notes References Sources External links Tapas, Birth, and Spiritual Rebirth in the Veda Walter O. Kaelber, History of Religions, 1976, The University of Chicago Press Tapas and Purification in Early Hinduism, Walter O. Kaelber, Numen, 1979, BRILL Tapas in Rigveda, Anthony Murdock, 1983, McMaster University Yoga, Meditation on Om, Tapas and Turiya in the Principal Upanishads, Ira Israel and Barbara Holdrege, 1999, UCSB Hindu philosophical concepts Meditation Yoga concepts Asceticism Hindu