nirgatena muner murdhnah
samiksya prabhavas trayah
tapyamanam—while practicing austerities; tri-bhuvanam—the three worlds; pranayama—practice by breathing exercise; edhasa—fuel; agnina—by the fire; nirgatena—issuing out; muneh—of the great sage; murdhnah—the top of the head; samiksya—looking over; prabhavah trayah—the three great gods (Brahma, Visnu and Mahesvara).
While Atri Muni was engaged in these severe austerities, a blazing fire came out of his head by virtue of his breathing exercise, and that fire was seen by the three principal deities of the three worlds.
According to Srila Jiva Gosvami, the fire of pranayama is mental satisfaction. That fire was perceived by the Supersoul, Visnu, and thereby Lord Brahma and Siva also perceived it. Atri Muni, by his breathing exercise, concentrated on the Supersoul, or the Lord of the universe. As confirmed in Bhagavad-gita, the Lord of the universe is Vasudeva (vasudevah sarvam iti [Bg. 7.19]), and, by the direction of Vasudeva, Lord Brahma and Lord Siva work. Therefore, on the direction of Vasudeva, both Lord Brahma and Lord Siva perceived the severe penance adopted by Atri Muni, and thus they were pleased to come down, as stated in the next verse.
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