Valmiki Ramayana Ayodhya Kanda Sarga 12 Shloka 106
Original Shlokaविनाऽपि सूर्येण भवेत्प्रवृत्तिरवर्षता वज्रधरेण वाऽपि। रामं तु गच्छन्तमित स्समीक्ष्य जीवेन्न कश्चित्त्विति चेतना मे।।2.12.106।।
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सूर्येण विनाऽपि even without the Sun, वज्रधरेण by Indra, wielder of the thunderbolt, अवर्षता वापि while not raining also, प्रवृत्ति: activity, भवेत् can happen, तु but, इतः from here, गच्छन्तम् while departing, रामम् Rama, समीक्ष्य having seen, कश्चित् any one, न जीवेत् will not live. इति this one, मे चेतना is my conviction.
Nature's activity will continue even without the Sun or even if Indra, wielder of the thunderbolt, sends no rain but none will live to see Rama departing to the forest. This is my conviction.