In contrasting tranquility (shanti) with hathapaka (forceful combustion), the commentator, Jayaratha, describes tranquility as a “process of pleasant combustion”. When the guru has been propitiated, the “tranquil” methods of initiation (diksasadhana) and devotion to a religious practice will bring about transcendence (atyaya) at the time of death. However, hathapaka is a sudden and violent process that burns up all things in the fire of intelligence. It destroys duality and is likened to the enjoyment of devouring enough. The commentator notes that hathapaka is a forceful action (balatkarena) that transgresses the normal order… This connotation of hatha is implicit in Hathayoga’s effect of raising the downward-moving breath (apana) and the normally dormant Kundalini.
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