SB 5.2.5
tasyah sulalita-gamana-pada-vinyasa-gati-vilasayas canupadam khana-khanayamana-rucira-caranabharana-svanam upakarnya naradeva-kumarah samadhi-yogenamilita-nayana-nalina-mukula-yugalam isad vikacayya vyacasta.
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
As Purvacitti passed by on the road in a very beautiful style and mood of her own, the pleasing ornaments on her ankles tinkled with her every step. Although Prince Agnidhra was controlling his senses, practicing yoga with half-open eyes, he could see her with his lotuslike eyes, and when he heard the sweet tinkling of her bangles, he opened his eyes slightly more and could see that she was just nearby.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
It is said that yogis always think of the Supreme Personality of Godhead within their hearts. Dhyanavasthita-tad-gatena manasa pasyanti yam yoginah (Bhag. 12.13.1). The Supreme Personality of Godhead is always observed by yogis who practice controlling the venomous senses. As recommended in Bhagavad-gita, yogis should practice sampreksya nasikagram, keeping their eyes half open. If the eyes are closed completely, there will be a tendency to sleep. So-called yogis sometimes practice a fashionable form of yoga by closing their eyes and meditating, but we have actually seen such so-called yogis sleeping and snoring while meditating. This is not the practice of yoga. To actually practice yoga, one should keep his eyes half open and gaze at the tip of his nose.
Although Agnidhra, the son of Priyavrata, was practicing mystic yoga and trying to control his senses, the tinkling sound of Purvacitti’s ankle bells disturbed his practice. Yoga indriya-samyamah: actual yoga practice means controlling the senses. One must practice mystic yoga to control the senses, but the sense control of a devotee who fully engages in the service of the Lord with his purified senses (hrsikena hrsikesa-sevanam) can never be disturbed. Srila Prabodhananda Sarasvati therefore stated, durdantendriya-kala-sarpa-patali protkhata-damstra-yate (Caitanya-candramrta 5). The practice of yoga is undoubtedly good because it controls the senses, which are like venomous serpents. When one engages in devotional service, however, completely employing all the activities of the senses in the service of the Lord, the venomous quality of the senses is completely nullified. It is explained that a serpent is to be feared because of its poison fangs, but if those fangs are broken, the serpent, although it seems fearsome, is not at all dangerous. Devotees, therefore, may see hundreds and thousands of beautiful women with fascinating bodily movements and gestures but not be allured, whereas such women would make ordinary yogis fall. Even the advanced yogi Visvamitra broke his mystic practice to unite with Menaka and beget a child known as Sakuntala. The practice of mystic yoga, therefore, is not sufficiently strong to control the senses. Another example is Prince Agnidhra, whose attention was drawn to the movements of Purvacitti, the Apsara, simply because he heard the tinkling of her ankle bells. In the same way that Visvamitra Muni was attracted by the tinkling bangles of Menaka, Prince Agnidhra, upon hearing the tinkling bangles of Purvacitti, immediately opened his eyes to see her beautiful movements as she walked. The prince was also very handsome. As described herein, his eyes were just like the buds of lotus flowers. As he opened his lotuslike eyes, he could immediately see that the Apsara was present by his side.