Some people, in their mistaken belief, associate the term tapasya with various practices of self-torture. But in reality, tapasya does not mean voluntarily living a life of isolation and hardship. Instead, it means leading a life of self-restraint and purity.
Tapasya, which is derived from the Sanskrit root word ‘tapa’ meaning heat or energy, has roughly been translated as austerities or penances. And a tapasvi, the one who engages in tapasya, has often been called an ascetic. But such translations do not bring out the real sense of these words. Tapasya is neither a form of self-denial nor a form of penance to atone for one’s sins. It, in fact, is the fine art of self-discipline. It refers to certain spiritual practices of self-regulation undertaken for purification of the body and the mind. As lustre of the gold increases in fire ; similarly the practice of tapasya makes one morally strong.
Bhagavad Gita has described three kinds of tapas - tapas of the body, tapas of the speech ; and tapas of the mind.
Reverence to the devas, to the dvija, to the guru and to the pragya ; and also cleanliness, straightforwardness, continence and non-violence - all these have been declared to be the tapas of the body. A tapasvi worships devas - the heavenly, divine beings who are the providers of knowledge and also various physical resources. The devas like Surya devta, Indra devta are benevolent supernatural beings who impact the human life in many ways.
The tapasvi also respects dvija, the twice born - the ones who having first born physically are born again spiritually.
They are the persons who have awakened inwardly. The one who is treading the path of tapasya also pays due regards to guru, the teacher - the one who gives spiritual guidance to his pupils.
A tapasvi revers the pragya - the sages who have fully realised their true nature. One can certainly be benefited by keeping the company and faithfully following the teachings of such men of wisdom.
The disciplines prescribed here are also an integral part of the tapas of the body. For any spiritual practice, more so for tapasya, cleanliness of the body is the first step. A tapasvi is also expected to be honest and upright in his dealings. Another discipline prescribed here is continence (brahmacharya) which means that a tapasvi should not be a slave to his sexual cravings. A tapasvi should also practice non-violence i.e. non-injury through thought, word and deed.
Along with the above tapasya of the body, Gita has enumerated the disciplines of speech. Speaking the words which are truthful and which give no offence to others, which are pleasant and which are beneficial ; and the practice of self-study - these are said to be the austerities of speech. Krishna has, thus, recommended regular introspection ; and speaking the truth, but without any harshness.
Apart from the austerities of the body and the speech, austerities of the mind have also been described in the Gita. Serenity of the mind, gentleness, silence, self-restraint ; and the purity of inner-thought - all these are said to be the austerities of mind. In other words, positive disposition of the mind towards oneself and also towards others is the tapasya of the mind.
Further, the three-fold tapasya of the body, speech and the mind has been categorised as per the modes of material nature (shlokas from 17.17 to 17.19).
The tapasya practiced with supreme faith and without expecting anything in return is called the tapasya in the mode of goodness (sattvic tapas). The austerities which are practiced with hypocrisy for the sake of respect, honour and worship is said to be in the mode of passion (rajasic tapas). Such tapasya is neither stable nor long lasting. And the tapasya which is performed with a foolish obstinacy involving self-torture or for causing harm to others, is said to be in the mode of ignorance (tamasic tapas).
Extreme ascetic practices have been decried in shlokas 17.5 and 17.6.
Those men who are full of hypocrisy and arrogance, and who impelled by the force of lust and attachment, practice severe austerities not ordained by the scriptures ; and thus torture all the physical elements in their bodies as well as the Supersoul dwelling within - such men have been declared to be the men of misled mentality and are known as demons. Krishna has, thus, condemned acts of self-torture performed by many for the purpose of display.
Whatever austerities one undertakes must be undertaken with steadfastness. Further, all austerities must be performed with full faith. The austerities performed without faith have been declared in the Gita to be false (asat). These are of no use either in this life or in the life hereafter.
In short, tapasya is a spiritual discipline which involves self-regulation, simplicity, moderate living and other means of self-purification. Such spiritual practices are one of the important means of realising the self.