Valmiki Ramayana Ayodhya Kanda Sarga 38 Shloka 7
Original Shlokaअजीवनार्हेण मया नृशंसा कृता प्रतिज्ञा नियमेन तावत्। तवया हि बाल्यात् प्रतिपन्नमेतत् तन्मां दहेद्वेणुमिवात्मपुष्पम्।।2.38.7।।
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अजीवनार्हेण unfit to live, मया by me, नियमेन with a vow, नृशंसा cruel, प्रतिज्ञा promise, कृता तावत् has been made, बाल्यात् out of childishness (foolishness), त्वया by you, एतत् this, प्रतिपन्नं हि was taken, तत् that one, वेणुम् bamboo, आत्मपुष्पम् इव like its own flowers, माम् me, दहेत् should burn.
By giving this cruel promise through importunity, I have rendered myself unfit to live. This promise was made as a child's play and it (now) destroys me like a bamboo destroyed by its own flowers.