Valmiki Ramayana Yuddha Kanda Sarga 2 Shloka 16
Original Shlokaशूराणांहिमनुष्याणांत्वद्विधानांमहात्मनाम् । विनष्टेवाप्रणष्टेवाशोकस्सर्वार्थनाशनः ।।6.2.16।।
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शूराणाम्: among the valiant ones, महात्मनाम्: great, त्वद्विधानाम्: that method, मनुष्याणाम्: by human being, विनष्टेवा: that which is destroyed, प्रणष्टेवा: or lost, शोकः worrying, सर्वार्थनाशनः leads to disaster of everything
"If you who are great among the valiant ones worry for that which is destroyed or lost, it would lead to disaster of everything."