Valmiki Ramayana Sundara Kanda Sarga 40 Shloka 18
Original Shlokaसाब्रवीद्दत्तमेवेति मयाभिज्ञानमुत्तमम्। एतदेव हि रामस्य दृष्ट्वा मत्केशभूषणम्।।5.40.18।। श्रद्धेयं हनुमन्वाक्यं तव वीर भविष्यति।
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मया mine, उत्तमम् best, अभिज्ञानम् identification, दत्तमेव already given, इति this, सा she, अब्रवीत् said, वीर hero, हनुमान् Hanuman, एतत् all this, मत्केशभूषणम् my jewel for the hair, दृष्ट्वा seeing, तव his, वाक्यम् words, रामस्य Rama's, श्रद्धेयम् what you tell, भविष्यति will believe.
"I have already given the best identification. When you hand this jewel used on my hair to him, he will believe what you tell him".