Valmiki Ramayana Yuddha Kanda Sarga 7 Shloka 20
Original Shlokaतिष्ठवाकिंमहाराजश्रमे णतववानरान् । अयमेकोमहाबाहुरिन्द्रजित्क्षपयिष्यति ।।6.7.20।।
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तिष्ठ: you stay, किम्: why, महाराज: Oh great king तव: your, श्रमेण: by exertion, वानरान्: the monkeys, अयम्: this, एको: alone, महाबाहु: strong armed, इन्द्रजित्: Indrajith (Elder son of Ravana) क्षपयिष्यति: can destroy.
"Oh great king, you stay here calmly. Why exert yourself? This strong armed Indrajith alone can destroy those Vanaras."