"Practice of Tapa", i.e., observance of austerities is one of the important supplements to Ahimsa-vrata which is considered useful in achieving Samvara, i.e., stoppage of influx of Karmic matter into the soul. These austerities are regarded as essential things for achieving Nirjara, i.e., the shedding of Karmic matter from the soul, which is a necessary condition to the attainment of Moksha, i. e., salvation. The Jaina scriptures distinguish twelve kinds of austerities, as the expedients of Nirjara, grouped together under the two headings of Bahya Tapa, i.e., external austerities, and Abhyantara Tapa, i.e., internal austerities.
The six external austerities are:
- Anasana, i.e., periodical fasting,
- Avamodarya, i.e., eating less than the capacity of the stomach,
- Vrtti-parisankhyana, i.e., putting restrictions in regard to food, for example, to accept food only if a certain condition is fulfilled.
- Rasa-parityaga, i.e., daily renunciation of one or more of six kinds of delicacies, viz., ghee, milk, curds, sugar, salt and oil,
- Vivikta-sayyasana, i. e., sitting or sleeping in a lonely or isolated place, devoid of animate beings, and
- Kayaklesa, i.e., mortification of the body so long as the mind is not disturbed.
The six internal austerities are:
- Prayaschitta, i.e., expiation,
- Vinaya, i.e., reverence,
- Vaiyavrtya, i.e., service of the saints or worthy people,
- Svadhyaya, i.e., study.
- Vyutsarga, i.e., giving up attachment to the body, etc., and
- Dhyana, i.e., concentration of mind.
All these external and internal kinds of austerities are practiced with the object of burning or shedding out all karmic impurities from the soul. These austerities are meant mainly for the ascetics, but it has also been enjoined upon the householders to practice them to the best of their abilities.