Valmiki Ramayana Kishkindha Kanda Sarga 53 Shloka 6
Original Shlokaएवमुक्ता हनुमता तापसी वाक्यमब्रवीत्। जीवता दुष्करं मन्ये प्रविष्टेन निवर्तितुम्।।4.53.6।।
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हनुमता by Hanuman, एवम् in that manner, उक्ता being told, तापसी ascetic, वाक्यम् these words, अब्रवीत् said, प्रविष्टेन by one who entered, जीवता with life, निवर्तितुम् to go back, दुष्करम् it is difficult, मन्ये I think.
To the words of Hanuman the ascetic replied, 'I consider it difficult for any one who enters here to go back alive.'