Valmiki Ramayana Yuddha Kanda Sarga 63 Shloka 18
Original Shlokaतान्भर्तामित्रसङ्काशानमित्रान्मन्त्रनिर्णये । व्यवहारेणजानीयात्सचिवानुपसम्हितान् ।।6.63.18।।
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भर्ता ruler, उपसम्हितान् who have become close to enemy, मित्रसङ्काशान् appearing as friends, अमित्रान् enemies, तान् they, सचिवान् ministers, मन्त्रनिर्णये through their behaviour, व्यवहारेण in deliberations, जानीयात् must know.
" A ruler should know those ministers bribed by the enemy, who have become close to the enemy and appear as friends. Those ministers must be known through their behaviour in the deliberations."