Valmiki Ramayana Ayodhya Kanda Sarga 46 Shloka 2
Original Shlokaइयमद्य निशा पूर्वा सौमित्रे प्रहिता वनम्। वनवासस्य भद्रं ते स नोत्कण्ठितुमर्हसि।।2.46.2।।
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सौमित्रे O Lakshmana, वनम् to the forest, प्रहिताः having been sent, अद्य today, इयम् this, वनवासस्य exile in the forest, पूर्वा first, निशा night, उत्कण्ठितुम् longing in your mind, न अर्हसि does not behove you, ते भद्रम् wish you well.
O Lakshmana, this happens to be the first night of our exile. You should not have any longing in your mind. Wish you well