“The sage Patanjali described a path with eight (ashta) limbs (anga) in order to quiet the mind and attain yoga or reunification with the Divine. Patanjali Yoga is called both Raja Yoga (The Royal Path) and Ashtanga Yoga (The Eight Limbs). The classical Ashtanga Yoga of Patanjali should not be mixed up with the modern proprietary form of yoga called Ashtanga Yoga which was developed by Pattabhi Jois.
The Yoga Sutras consist of 195 sutras that, if understood and practiced, lead to a “reunion” with the ultimate reality. A sutra is the thread of an idea usually expressed as a single sentence but may string together into two or three sentences. The sutras constitute an outline of the science. Before there were books, sutras were memorized and teachers would expound upon them. The date that Patanjali lived is unknown but is believed to be before 300 CE, as important commentaries on his writings, such as Vyasa’s Yoga Bhasya, are available beginning in the 4th century. Patanjali’s approach to yoga adopts the cosmic world view of Sankhya philosophy and develops a technique for transcending the limited ahamkara (ego) and returning the soul (atman) to Purusha.
The most important tenet of the Yoga Sutras is found in the second sutra (statement) of the first section of the text: “Yoga chitta vritti nirodha.” It is very famous. This sutra means that yoga (union) is achieved when the disturbances (vritti) of the mind (chitta) are eradicated (nirodha). The rest of the Yoga Sutras are instructions regarding how to quiet the mind and attain this state of yoga.”
~ Excerpt from “Principles of Ayurvedic Medicine,” by Dr. Marc Halpern, Founder of the California College of Ayurveda