The term “tapas” or “tapasya” in Sanskrit represents an essential concept in the practice of Yoga. ordinarily translated as “austerity” or “askesis”, the term has a much more essential sense to it, akin to the concept of “will” or “concentration in thought”, the focused and one-pointed gathering of the faculties to allow a breakthrough in understanding beyond the limits of body, life and the normal actions of the mind.
In the Taittiriya Upanishad, when Bhrigu asked his father Varuna to teach him the Eternal, at each stage of his growth in understanding, Varuna replied “By askesis (tapas) do thou seek to know the Eternal, for askesis is the Eternal.” When we reflect on the significance of this, we find that this power focusing of the deeper will, not what we ordinarily call the exercise of will in the mental framework, acts as the unifying power between the individual and the Supreme. (Bhriguvalli)
In another section, the process of the creation of the universe is characterized as the Spirit concentrating “all Himself in thought, and by the force of His brooding He created all this universe, yea, all whatsoever existeth.” (Sri Aurobindo, The Upanishads, Taittiriya Upanishad, Brahmanandavalli, Chapter 6, pg. 270)
The human being generally is considered to be guided by his mental faculties, at the highest levels of human capacity. The formula in the ancient texts is on the order of “the mind, the leader of the life and body.” Sri Aurobindo observes, however, that this is only true for the outer personality. The mind is not the instrument that can associate itself with the Supreme directly. The mind “turns back without attaining” in the language of the Upanishad.
Sri Aurobindo explores the deeper meaning of “will” in this sense: “This Will is not the wish of the heart or the demand or preference of the mind to which we often give the name. It is that inmost, dominant and often veiled conscious force of our being and of all being, Tapas, Shakti, Shraddha, that sovereignly determines our orientation and of which the intellect and the heart are more or less blind and automatic servants and instruments.”
The manifestation of the universe is carried out through the Will of the Supreme. “In these activities is expressed the conscious Will of Shakti of the Spirit moved to manifest its being in infinite ways, a Will or Power not ignorant but at one with its own self-knowledge and its knowledge of all that it is put out to express. And of this Power a secret spiritual will and soul-faith in us, the dominant hidden force of our nature, is the individual instrument, more nearly in communication with the Supreme, a surer guide and enlightener, could we once get at it and hold it, because profounder and more intimately near to the Identical and Absolute than the surface activities of our thought powers. To know that will in ourselves and in the universe and follow it to its divine finalities, whatever these may be, must surely be the highest way and truest culmination for knowledge as for works, for the seeker in life and for the seeker in Yoga.”
Sri Aurobindo, The Synthesis of Yoga, Part Two: The Yoga of Integral Knowledge, Chapter 1, The Object of Knowledge, pp. 275-276