Valmiki Ramayana Yuddha Kanda Sarga 87 Shloka 29
Original Shlokaधर्षयित्वा च काकुत्स्थं न शक्यंजीवितुंत्वया । युध्यस्वनरदेवेनलक्ष्मणेनरणेसह ।।6.87.29।। हतस्त्वंदेवताकार्यंकरिष्यसियमक्षये ।
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काकुत्स्थम् Kakuthsa, धर्षयित्वा clashing, त्वया by you, जीवितुम् life, न शक्यम् not possible, रणए in combat, नरदेवेन god of retribution, लक्ष्मणेनसहस with Lakshmana, युध्यस्व waging war, त्वम् you, हतः killed, यमक्षये abode of yama, देवताकार्यम् tasks of Devatas, करिष्यसि will be doing
"Clashing with Lakshmana of Kakuthsa clan is not possible for you. By waging war with Lakshmana, you will be killed and reaching the abode of the Lord of death. You will be doing tasks of deities of Devatas."