What It Means:
Wikipedia: Pratyahara is derived from two Sanskrit words: prati and ahara, with ahara meaning food, or anything taken into ourselves, and prati, a preposition meaning away or against. Together they mean "weaning away from ahara," or simply ingestion.
Pratyahara (Devanāgarī प्रत्याहार, Tibetan སོ་སོར་སྡུད་པ་) or the "withdrawal of the senses" is the fifth element among the Eight stages of Patanjali's Ashtanga Yoga, as mentioned in his classical work, Yoga Sutras of Patanjali composed in the 2nd century BCE. It is also the first stage of the six branch yoga of the Buddhist Kālacakra tantra, where it refers to the withdrawal of the five senses from external objects to be replaced by the mentally created senses of an enlightened deity.
"Pratyahara itself is termed as Yoga, as it is the most important limb in Yoga Sadhana."- Swami Shivananda
According to Patanjali's Yoga Sutras, Pratyahara is the bridge between the external aspects of yoga and the internal stages of yoga. Once a yoga practitioner is able to actualize Pratyahara, he is able to engage in Samyama.
In pratyahara, the consciousness of the person is internalized so that he does not experience the sense of taste, touch, sight, hearing and smell, taking the practitioner to the next stages of yoga – Dharana (concentration), Dhyana (meditation) and Samadhi (mystical absorption), which is the aim of all yogic practices.
There are two types of Pratyahara. The first is the withdrawal of senses or "Indriya Pratyahara." The second is the withdrawal of prana or "Prana Pratyahara," in which a person's focus is placed on one specific part of the body. The focus is usually placed on the third eye.
Pratyahara centers on the rightful intake of impressions, which is food for the mind. While people tend to focus on the impressions food or exercise has on the body, they tend to forget the impact of the media and other external influences. Pratyahara is about removing these influences into the sense.
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