sulalita dīrghārgala, kṛṣṇera bhuja-yugala,
dui śaila-chidre paiśe, nārīra hṛdaye daṁśe,
mare nārī se viṣa-jvālāya
su-lalita—very beautiful; dīrgha-argala—long bolts; kṛṣṇera—of Kṛṣṇa; bhuja-yugala—two arms; bhuja—arms; nahe—not; kṛṣṇa—black; sarpa—of snakes; kāya—bodies; dui—two; śaila-chidre—in the space between the hills; paiśe—enter; nārīra—of women; hṛdaye—the hearts; daṁśe—bite; mare—die; nārī—women; se—that; viṣa-jvālāya—from the burning of the poison.
"The two very beautiful arms of Kṛṣṇa are just like long bolts. They also resemble the bodies of black snakes that enter the space between the two hill-like breasts of women and bite their hearts. The women then die from the burning poison.
In other words, the gopīs become very agitated by lusty desires; they are burning due to the poisonous bite inflicted by the black snakes of Kṛṣṇa's beautiful arms.
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