Valmiki Ramayana Bala Kanda Sarga 75 Shloka 7
Original Shlokaभार्गवाणां कुले जात: स्वाध्यायव्रतशालिनाम्। सहास्राक्षे प्रतिज्ञाय शस्त्रं निक्षिप्तवानसि।।1.75.7।।
1 source checked for this shloka
स्वाध्यायव्रतशालिनाम् resplendent with the study of vedas and observance of vows, भार्गवाणाम् relating to Bhargavas, कुले in the race of, जात: was born, सहास्राक्षे in the name of Indra, प्रतिज्ञाय having vowed, शस्त्रं arms, निक्षिप्तवान् असि have renounced.
Born in the family of (saint) Bhrigu versed in the study of the Vedas and observance of vows. You have promised in the name of the thousandeyed Indra to renounce the arms.