Valmiki Ramayana Sundara Kanda Sarga 39 Shloka 11
Original Shlokaनित्यमुत्साहयुक्ताश्च वाचश्रुत्वा त्वयेरिताः। वर्धिष्यते दाशरथेः पौरुषं मदवाप्तये।।5.39.11।।
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त्वया you, ईरिताः spoken, उत्साहयुक्ताः full of determination for action, वाचः words, नित्यम् ever, श्रुत्वा after hearing, मदवाप्तये for acquiring me, दाशरथेः son of Dasaratha, पौरुषम् manliness, वर्धिष्यते will increase.
"On hearing your ever spirited words his manliness to get me back will be charged.