A VERY BRIEF bit of background on the Yoga Sūtras of Patañjali:
(Note: The quoted text is from Iyengar, B.K.S. (1993). Light on the Yoga Sūtras of Patañjali. Hammersmith, London: Harper Collins.)
This is an ancient text attributed to a historical figure named Patañjali who lived sometime between 500 CE and 200 BCE. It is a collection of 196 sūtras (aphorisms, or literally “threads”) divided into four pādas (“parts”). It is widely regarded as the most important text on yoga philosophy and there are countless translations and commentaries.
The first part, Samādhi Pāda, addresses the ultimate goal of yoga practice, samādhi. Iyengar describes samādhi as “seeing the soul face to face, an absolute, indivisible state of existence, in which all differences between body, mind, and soul are dissolved” (p. 4). So this first part of the Sūtras is thought to be directed at readers who are already far along the path.
The second part, Sādhana Pāda, is for those new to the path of yoga. Here Patañjali lays out the practice of yoga (sādhana means “practice”) based on the eight “limbs”, or eight “yogic disciplines”: yama, niyama, āsana, prānāyāma, pratyāhāra, dhāranā, dhyāna, and samādhi.
In the third section, Vibhūti Pāda, Patañjali describes the superpowers that can be achieved through yoga practice and advises against getting sidetracked by the lure of these powers.
The fourth and final section is titled Kaivalya Pāda. It offers the reader a more fine-tuned understanding of the ultimate fruits of yoga practice. According to Iyengar, in this chapter “Patañjali distinguishes kaivalya from samādhi. In samādhi, the sādhaka (practitioner) experiences a state of passive oneness between seer and seen, observer and observed, subject and object. In kaivalya, he lives in a positive state of life…The yogi lives in the experience of wisdom, untinged by the emotions of desire, anger, greed, infatuation, pride, and malice…He is immersed in kaivalya, the constant burning light of the soul, illuminating the divinity not only in himself, but also in those who come in contact with him” (pp. 8-9).