vajras tu tat-kandharam asu-vegah
krntan samantat parivartamanah
nyapatayat tavad ahar-ganena
yo jyotisam ayane vartra-hatye
vajrah—the thunderbolt; tu—but; tat-kandharam—his neck; asu-vegah—although very fast; krntan—cutting; samantat—all around; parivartamanah—revolving; nyapatayat—caused to fall; tavat—so many; ahah-ganena—by days; yah—which; jyotisam—of the luminaries like the sun and moon; ayane—in moving to both sides of the equator; vartra-hatye—at the time suitable for killing Vrtrasura.
Although the thunderbolt revolved around Vrtrasura’s neck with great speed, separating his head from his body took one complete year—360 days, the time in which the sun, moon and other luminaries complete a northern and southern journey. Then, at the suitable time for Vrtrasura to be killed, his head fell to the ground.
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