Series 1, Chapter 12 pg 121, Para 1: But all even of the Yogins have not attained to this knowledge. “Some Yogins follow after the sacrifice which is of the gods; others offer the sacrifice by the sacrifice itself into the Brahman-fire.” The former conceive of the Divine in various forms and powers and seek him by various means, ordinances, dharmas, laws or, as we might say, settled rites of action, self-discipline, consecrated works; for the latter, those who already know, the simple fact of sacrifice, of offering whatever work to the Divine itself, of casting all their activities into the unified divine consciousness and energy, is their one means, their one dharma. The means of sacrifice are various; the offerings are of many kinds. There is the psychological sacrifice of self-control and self-discipline which leads to the higher self-possession and self-knowledge. “Some offer their senses into the fires of control, others offer the objects of sense into the fires of sense, and others offer all the actions of the sense and all the actions of the vital force into the fire of the Yoga of self-control kindled by knowledge.” There is, that is to say, the discipline which receives the objects of sense-perception without allowing the mind to be disturbed or affected by its sense-activities, the senses themselves becoming pure fires of sacrifice; there is the discipline which stills the senses so that the soul in its purity may appear from behind the veil of mind-action, calm and still; there is the discipline by which, when the self is known, all the actions of the sense-perceptions and all the action of the vital being are received into that one still and tranquil soul. The offering of the striver after perfection may be material and physical, dravya-yajna, like that consecrated in worship by the devotee to his deity, or it may be the austerity of his self-discipline and energy of his soul directed to some high aim, tapo-yajna, or it may be some form of Yoga like the Pranayama of the Rajayogins and Hathayogins, or any other yoga-yajna. All these tend to the purification of the being; all sacrifice is a way towards the attainment of the highest.

Series 3, Chapter 4 pg 598, Para 28: 28. The offering of the striver after perfection may be material and physical (dravyayajna, like that consecrated in worship by the devotee to his deity), or it may be the austerity of his self-discipline and energy of his soul directed to some high aim, tapo-yajna, or it may be some form of Yoga (like the Pranayama of the Raja-yogins and Hatha-yogins, or any other yoga-yajna), or it may be the offering of reading and knowledge.