Valmiki Ramayana Aranya Kanda Sarga 14 Shloka 2
Original Shlokaतं दृष्ट्वा तौ महाभागौ वटस्थं रामलक्ष्मणौ। मेनाते राक्षसं पक्षिं ब्रुवाणौ को भवानिति।।3.14.2।।
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महाभागौ both the venerable, तौ रामलक्ष्मणौ Rama and Lakshmana, वटस्थम् on the banyan tree, तं पक्षिम् that bird, दृष्ट्वा on seeing, भवान् you, कः who are, इति this way, ब्रुवाणौ (while) saying so, राक्षसम् demon, मेनाते thought.
Seeing the bird on the banyan tree, venerable Rama and Lakshmana mistook him for a demon and enquired who he was.