Valmiki Ramayana Aranya Kanda Sarga 45 Shloka 1
Original Shlokaआर्तस्वरं तु तं भर्तुर्विज्ञाय सदृशं वने। उवाच लक्ष्मणं सीता गच्छ जीनीहि राघवम्।।3.45.1।।
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सीता Sita, वने in the forest, भर्तुः husband, सदृशम् similar, तम् that, आर्तस्वरम् voice in distress, विज्ञाय knowing, लक्ष्मणम् to Lakshmana, उवाच said, गच्छ go, राघवम् Rama, जानीहि know (what happened).
On hearing the voice in distress and recognising that it was similar to her husband's voice, Sita said to Lakshmana, 'Go and find out Rama's whereabouts'. There at the hermitage Sita asks Lakshmana to rush to Rama's help Lakshmana resists, stating Rama needs no help--Sita lashes at Lakshmana in harsh words.