Valmiki Ramayana Sundara Kanda Sarga 30 Shloka 37
Original Shlokaभूताश्चार्था विनश्यन्ति देशकालविरोधिताः।।5.30.37।। विक्लबं दूतमासाद्य तमः सूर्योदये यथा।
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विक्लबम् a confused person, दूतम् messenger, आसाद्य by appointing, भूताः even sure ones, अर्थाः missions, देशकालविरोधिताः if place and time are not propitious, सूर्योदये at Sunrise, तमः यथा like the darkness, विनश्यन्ति will be destroyed.
"Even well planned diplomatic missions fail like darkness dispelled at Sunrise if the messenger is confused and if the place and time are not propitious for them.