49th Sutra Chapter 2: c
Pranayama is mastery of Pran, the universal life force, through the breath.
Pranayama is considered in our Scriptures as Param Tapa that is the highest form of Tapa practice, that purifies all impurities in the body and the mind.
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तस्मिन् सति श्वासप्रश्वासयोर्गतिविच्छेदः प्राणायामः
tasmin: on this
sati: being accomplished
shvaasa: inhalation
prashvaasayoh: exhalation
gati: movement
vichChedaH: regulation;
prana: cosmic energy
ayama: churning
praaNaayaamaH: regulation of breath
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