DISCIPLINE FOR SADHANA- Tapahsvadhyayesvrapranidhanani kriyayogah. Tapah: austerity; svadhyaya: self-study of scriptures; ishvara pranidhana: surrender to God; kriya yoga: practical yoga. Tapas, swadhyaya & Ishwara pranidhana constitue kriya yoga. The word tapas literally means to burn, to create heat or to produce energy. Usually tapas is translated as ascetiism, austerity or penance, but really it means a process which completely illuminates the imperfections, the dross of the inner personality. It is said in the Bhagavad Gita that the fire of jnana burns the entire stock fo ktock of karma, the current karmas & the karmas that are already sacrificed. It is said by Nagarjuna that a seed when not burnt is capable of giving rise to many seeds & plants. In the same way, when the chitta is not freed from the samskaras, it is capable of producing many more samskaras, bodies & reincarnations. A roasted or burnt seed becomes incapable of reproducing. This process is tapas, which involves self-purification. Sometimes the impurity is small & needs very little washing, but when avidya is too much, it becomes necessary to put the material impressions into a fire. Tapas is a sadhana which cleans sn extremely dirty mind full of avidya. Tapas also means conservation of heat & energy. It even creates physical heat, as in pranayama. The word tapas is used here in a very high context. In sutra 32 of this chapter, the word tapas will occur. There it will be an elementary sadhana. In this sutra, tapas is not used in the sense of austerity or penance, but in the sense of generating a kind of heat. That heat can be generated by pranayama, hatha yoga, mudras & bandhas, by concentration of mind, by brahmacharya, of ahimas. It is not only physical heat, it is also pranic heat, meantal heat, or spiritual heat. It has a psychic nature.