The Sanskrit verb yuj—the root of the word “yoga”—means “to yoke or harness.” In everyday language, yuj assumed the sense of “unite, connect, add, bring together,” as well as “make ready, prepare, set to work, employ, apply.” Thus, in much of the sacred literature of India, yoga signifies the aim of uniting (or, more accurately, reuniting) the individual soul and the universal soul (Brahman) as well as the preparatory work necessary to bring about this union.
Its oldest application is a relic of a time about 3,500 years ago when Indian warriors rode into battle on chariots. These vehicles typically carried an archer and his driver or charioteer and were drawn by two horses, who had the reputation of being ferocious. “At his deep neigh,” sings one old hymn about the cry of a war horse, “like the thunder of heaven/the foemen tremble in fear.” The charioteer, whose task it was to hitch these spirited beasts to the chariot, needed extraordinary bravery and skill and, as a consequence, his position was highly esteemed.
But the word “yoga” is remarkably flexible and refuses to be bound to one narrow definition. In the classical school of Patanjali, in contrast, yoga is defined as the “restriction of the fluctuations of consciousness,” which is the difficult and risky job of securing the harness on the unruly “horses,” meaning the skittish thoughts and rearing emotions of the mind.