In India physical methods have been used for religious ends since at least 1000 bce. For two millennia these methods were simple techniques of privation in which the body was mortified, usually by holding a particular posture for long periods, in order to acquire tapas, ascetic power. The details of their performance were not transmitted in texts but, we must assume, passed on orally within lineages of renouncer ascetics. In the early part of the second millennium ce, a somatic soteriology whose physical methods are body-affirming appears in textual sources; some of its practices are depicted soon after in the material record. In certain Sanskrit texts these methods of yoga were classified as haṭha, which means “force”; haṭhayoga means “yog...