Valmiki Ramayana Kishkindha Kanda Sarga 34 Shloka 8
Original Shlokaयस्तु राजा स्थितोऽधर्मे मित्राणामुपकारिणाम्। मिथ्या प्रतिज्ञां कुरुते को नृशंसतरस्ततः।।4.34.8।।
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यः whoever, राजा a king, अधर्मे in unrighteous path, स्थितः adopts, उपकारिणाम् to his benefactors, मिथ्या false, प्रतिज्ञाम् promise, कुरुते makes, ततः then, नृशंसतरः more malicious, कः what
'Which king can be more malicious than the one who makes false promises and adopts an unrighteous path towards those who helped him?