Chapter-3, Sutra 21

Patanjali Yogasutra 3.21

कायरूपसंयमात्तद्ग्राह्यशक्तिस्तम्भे चक्षुःप्रकाशासंप्रयोगेऽन्तर्धानम् ॥

"By performing saṁyama (perfect concentration) on the form of the body, when the power of perception is suspended, the connection between the eye and light is severed, and the body becomes invisible."

Patanjali describes a subtle and advanced siddhi (spiritual power) in this Sutra that relates to controlling one's perception. Here, when a yogi performs saṁyama on their physical form, they develop the ability to manipulate their own body's perceptibility. By controlling the "grasping power" of the senses, particularly vision, the yogi can create the condition for invisibility. It essentially means that the body does not get perceived, as the connection between the observer's eyes and the light reflected off the yogi's body is interrupted.

This antardhānam (disappearance) highlights the yogic idea that what is perceived in the world is dependent on the senses' interaction with objects. Patanjali teaches that by breaking this connection through focused practice, a yogi can defy common physical limitations. The ability to disappear is not literal in the sense of ceasing to exist, but rather a result of manipulating how others perceive the yogi's presence. The Sutra underscores the power of the mind and its control over physical reality.

From a broader perspective, this verse shows that our physical Reality is subject to mental mastery. The "light" of perception does not belong solely to the external world but is intimately connected with the mind and its control over sensory input. This Sutra is also symbolic of the deeper spiritual goal in yoga: to transcend material appearances and understand the deeper, formless Reality of existence.

Swami Vivekanand said:

"A Yogi standing in the midst of this room can apparently vanish. He does not really vanish, but he will not be seen by anyone. The form and the body are, as it were, separated. You must remember that this can only be done when the Yogi has attained to that power of concentration when form and the thing formed have been separated. Then he makes a Samyama on that, and the power to perceive forms is obstructed, because the power of perceiving forms comes from the junction of form and the thing formed."

Comparison with Vedic Texts:

Mundaka Upanishad 3.1.8:

स यो ह वै तत्परं ब्रह्म वेद ब्रह्मैव भवति । नास्याभ्रमवित् कुतश्चन । आत्मन्येवात्मानं पश्यति सर्वं चात्मन्येव पश्यति ॥

"He who knows the Supreme Brahman becomes Brahman indeed. No one who does not know the Supreme can become Brahman. He perceives everything in himself and sees everything as his own Self."

This verse from the Mundaka Upanishad speaks to the Ultimate Realization of Self, where the distinction between Self and the external world disappears. This parallels Patanjali’s teaching in that the yogi's mastery over perception can extend to Realizing that the Self, in its true essence, transcends physical form and the limitations of sensory perception. The connection lies in how perception shapes Reality, and true Spiritual Realization dissolves this duality.

Yoga Vashishta 6.1.34

इन्द्रियाणां विनाशेन देहस्य स्थूलसंविधः । 

न दृश्यं भवति स्थाणौ स्थाणुवद्भाति केवलम् ॥

"With the dissolution of the senses, the gross body loses its visibility. It appears just like a tree trunk, without perception."

This verse from the Yoga Vashishta shares a direct thematic link to Patanjali's Sutra. Here, the dissolution of sensory faculties leads to the gross body's disappearance, reflecting the idea that visibility is a construct of sensory perception. Once the senses, particularly vision, cease to function in their typical way, the body is no longer perceived.

Rig Veda 10.129.4

अदर्शि तन्नाध्र्ष्य तन्मसिरं तन्वन्नाशः ॥

"What was hidden, what was ungraspable, became manifest, though imperceptible, it remained."

This verse from the Rig Veda reflects the mystical notion of hidden realities that are beyond ordinary perception. 

Similar to Patanjali’s teaching, it emphasizes that things can exist but remain beyond the reach of human senses unless deeper insight or mastery is gained.

Together, these references illustrate a common theme across Vedic and yogic traditions: perception and Reality are not fixed. With deep spiritual or yogic practice, one can transcend the ordinary functioning of the senses and experience the world in an entirely different, often incomprehensible way to the untrained mind. Patanjali’s Sutra encapsulates the same idea but with a focus on the practical application of yogic powers, showing how perception shapes our Reality.