“By practice of Pranayama the dross of the nadis are eliminated from the body through the many channels. It can be concluded that the toxins in the body are removed if one’s inhalation exhalation and retention are long, even and effortless.”

 - Yoga Rahasya - 

“‘Cessation’ (nirodha) of the mind was taught by previous masters [like Patanjali] through the yoga of renunciation [of the mind and senses] and arduous practice. Here I will teach a cessation that is effortless.”

 - Svabodhodaya mañjarī - 

“Always or during the three Sandhis (morning, afternoon and evening), practice the control of Prana. All those who practice Pranayama regularly who regard Pranayama as their goal and who have been purified through Pranayama, attain liberation.”

 - Yoga Yajnavalkya -