Valmiki Ramayana Yuddha Kanda Sarga 63 Shloka 20
Original Shlokaयोहिशत्रुमवज्ञायनात्मानमभिरक्षति । अवाप्नोतिहिसोऽनर्थान् स्थानाच्चव्यवरोप्यते ।।6.63.20।।
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यः he who, शत्रुम् enemy, अवज्ञाय knowing fully, आत्मानम् himself, नाभिरक्षति does not protect himself, सः he, अनर्थान् reverses, अवाप्नोतिहि attains, स्थानात् from position, व्यवरोप्यते च is dragged
"He who knowing fully the actions of the enemy does not protect himself he attains reverses and is also dragged down from position."