Yoga-siddhi — The Mystic Perfections and Their Origin in Meditation on the Lord
परकायं विशन् सिद्ध आत्मानं तत्र भावयेत् । पिण्डं हित्वा विशेत् प्राणो वायुभूत: षडङ्घ्रिवत् ॥ २३ ॥
para-kāyaṁ viśan siddha ātmānaṁ tatra bhāvayet piṇḍaṁ hitvā viśet prāṇo vāyu-bhūtaḥ ṣaḍaṅghri-vat
成就したヨーギーが他者の身体に入ろうとするなら、その身体の内に自分があると観想し、ついで自らの粗大な身体を捨て、風となったプラーナの通路を通って入るべきである。それは蜂が一つの花を離れて別の花へ移るほど容易である。
As air is inhaled into the body through the nostrils and mouth, similarly, the life air of the yogī’s subtle body travels through the pathways of external air and easily enters into the body of another person, just as the bee easily flies from flower to flower. One may admire a heroic man or beautiful woman and desire to experience life within their extraordinary material body. Such opportunities are available through the mystic perfection called para-kāya-praveśanam. Pure devotees, being absorbed in meditation upon the spiritual form of the Supreme Personality of Godhead, are not actually attracted to any material body. Thus the devotees remain transcendental and satisfied on the platform of eternal life.
In Canto 11, Chapter 15, Kṛṣṇa describes that a perfected yogī can enter another body by fixing his consciousness there and then letting the life-air, made subtle like wind, pass into that body.
While teaching Uddhava the paths of yoga and devotion, Kṛṣṇa explains various yogic perfections and their methods, clarifying their mechanics and implicitly showing that such powers are secondary to pure bhakti.
Rather than seeking supernatural powers, one can apply the principle of disciplined focus—training the mind and life-force through sādhana—while keeping devotion and ethical restraint as the true spiritual priority.