1. What Is Pratyahara
Pratyahara or abstraction is that by which the senses do not associate with their own objects and imitate, as it were, the nature of the mind-stuff (Chitta).
Pratyahara is abstraction. It is the withdrawal of the Indriyas from the objects. The senses are assimilated in the mind which is rendered pure through the practice of Yama, Niyama and Pranayama. The mind becomes more calm now. The nature of the Indriyas is to have always connection with the objects. Where the vision is turned outward (Bahirmukha Vritti), the rush of fleeting events engages the mind. The outgoing energies of the mind begin to play. When they are obstructed by the practice of Pratyahara, the other course for them is to mix with the mind and to be absorbed in the mind. The mind will not assume any form of any object. Hitherto, the Indriyas were following the mind like the other bees which follow the queen bee. Just as the bees fly as the queen bee flies, and sit as it sits down, so also, the Indriyas become restrained as the mind is restrained.
Pratyahara itself is termed as Yoga, as it is the most important Anga in Yoga Sadhana. This is the fifth rung in the Yogic ladder. The first four rungs deal with ethical training and purification of body, mind and Nadis. Now with Pratyahara, proper Yoga begins which eventually culminates in Dharana, Dhyana and Samadhi. Hence in Kathopanishad also in Part VI, Sloka 11, you will find: That firm control of the senses, they regard as Yoga. Again in the same Upanishad it is stated in Part IV, Sloka 1: The Self-existent created the senses outgoing, therefore, one sees outside and not the Atman within. Some intelligent man, with his senses turned away from their object, desirous of immortality, sees the Atman within.
2. Benefits of Pratyahara
Thence (from the practice of Pratyahara), comes the supreme mastery over the senses.
Yogins enjoy sound, etc., without Raga and Dvesha. Worldly persons enjoy with Raga and Dvesha. This is the difference. The Yogi, not becoming a slave of the Vishayas, enjoys as a master out of his own free will. The Yogi enjoys by remaining as Tatastha (quite indifferent) with Raga and Dvesha experiencing the effects viz., pleasure and pain. The Indriyas cannot grasp the objects even though they are placed before them. This is Indriya Jaya. There is a difference between control and supreme control. By controlling one Indriya alone, the other four will not come under your control. When the mind is rendered pure and one-pointed and when it is turned inwards towards the Purusha, then and then alone supreme control of all organs follows.
He who has practised Pratyahara can have good concentration and meditation. His mind is always peaceful. This demands patience and constant practice. It takes some years before one is well-established in Pratyahara. He who has mastery over Pratyahara will never complain of Vikshepa or distraction of mind. He can sit in a place in a busy city where four roads meet and meditate whenever he likes. He does not want a cave for meditation. Just as the tortoise draws in on all sides its limbs, so also, the Yogi withdraws all his senses from the objects of sense through the practice of Pratyahara. Pratyahara gives power to the practitioner. When the Indriyas are withdrawn from the objects, then you can fix the mind on a particular point. It is Dharana or concentration which is dealt with in the next chapter. Pratyahara and Dharana are interdependent. You cannot practise one without the other.