kṛṣṇa-śaktye prakṛti haya gauṇa kāraṇa
agni-śaktye lauha yaiche karaye jāraṇa
kṛṣṇa-śaktye—by the energy of Kṛṣṇa; prakṛti—the material nature; haya—becomes; gauṇa—indirect; kāraṇa—cause; agni-śaktye—by the energy of fire; lauha—iron; yaiche—just as; karaye—becomes; jāraṇa—powerful or red-hot.
Thus prakṛti, by the energy of Lord Kṛṣṇa, becomes the secondary cause, just as iron becomes red-hot by the energy of fire.
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