Valmiki Ramayana Ayodhya Kanda Sarga 27 Shloka 6
Original Shlokaयदि त्वं प्रस्थितो दुर्गं वनमद्यैव राघव। अग्रतस्ते गमिष्यामि मृद्नन्ती कुशकण्टकान्।।2.27.6।।
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राघव son of the Raghus (Rama), अद्यैव now itself, त्वम् you, दुर्गम् impenetrable, वनम् forest, प्रस्थितः यदि if you set out, कुशकण्टकान् on thorns and on Kusa grass, मृद्नन्ती crushing, ते अग्रतः in front of you, गमिष्यामि I shall go.
O son of the Raghus if you set out for the impenetrable forest now itself, I shall also go, walking ahead of you and crushing the thorns and (spiky) kusa grass (rendering the path comfortable for you to walk).