Valmiki Ramayana Yuddha Kanda Sarga 73 Shloka 18
Original Shlokaत्वमप्रतिरथःपुत्रत्वयावैवासवोजितः । किम्पुनर्मानुषंधृष्यंनिहनिष्यसिराघवम् ।।6.73.18।। तथोक्तोराक्षसेन्द्रेणप्रत्यगृह्णान्महाशिषः ।
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पुत्र son, त्वम् you, अप्रतिरथः an adversary in fighting sitting in a war chariot, त्वया by you, वासवः Indra, जितः won, मानुषम् mortals, धृष्यम् to assail, राघवम् Raghava, निहनिष्यसि killing, किम् पुनः why to speak again, राक्षसेन्द्रेण Rakshasa king, तथा that way, उक्तः spoke, महाशिषः mighty blessings, प्रत्यगृह्णात् accepted.
"Son! there is no adversary who can fight with you sitting in a chariot. Indra has been won by you. What to say about mortals like Rama who can be assailed by you."Rakshasa king having spoken that way, Indrajith accepted the blessings and departed.