Valmiki Ramayana Sundara Kanda Sarga 37 Shloka 15
Original Shlokaन स शक्यस्तुलयितुं व्यसनैः पुरुषर्षभः। अहं तस्य प्रभावज्ञा शक्रस्येव पुलोमजा ।।5.37.15।।
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पुरुषर्षभः bull among men, सः he, व्यसनैः in calamities, तुलयितुम् shaken, न शक्यः not possible, पुलोमजा daughter of Puloma, शक्रस्येव just as Indra, अहम् I, तस्य his, प्रभावज्ञा know his might.
"O bull among men he will not be shaken by calamities. Just as Sachi, the daughter of Puloma knows Indra's might I know Rama's.