Valmiki Ramayana Bala Kanda Sarga 39 Shloka 9
Original Shlokaअयं पर्वणि वेगेन यज्ञियाश्वोऽपनीयते। हर्तारं जहि काकुत्स्थ हयश्चैवोपनीयताम्।।1.39.9।।
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काकुत्स्थ O Kakutstha, king Sagara, पर्वणि on this auspicious Parvan day, अयं यज्ञियाश्व: this sacrificial horse, वेगेन quickly, अपनीयते forcibly is being taken away, हर्तारम् the thief, जहि slay him, हयश्च horse, उपनीयताम् be brought back.
'O Kakutstha on this auspicious (fullmoon) day the sacrificial horse has been stolen away suddenly and forcibly. Slay the thief and bring back the horse'.