Valmiki Ramayana Ayodhya Kanda Sarga 23 Shloka 37
Original Shlokaअद्य मेऽस्त्रप्रभावस्य प्रभावः प्रभविष्यति। राज्ञश्चाप्रभुतां कर्तुं प्रभुत्वं तव च प्रभोः।।2.23.37।।
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प्रभो O Lord, अद्य today, मे my, अस्त्रप्रभावस्य of glorious weapons, प्रभावः strength, राज्ञः of the king (Dasaratha), अप्रभुताम् having no power over the kingdom, तव your, प्रभुत्वं च supremacy over the kingdom, कर्तुम् to make, प्रभविष्यति is competent.
O Lord today you shall see the power of my glorious weapons in depriving the king (Dasaratha) of his authority and establishing your supremacy over the kingdom.