Valmiki Ramayana Ayodhya Kanda Sarga 25 Shloka 35
Original Shlokaत्रीन्विक्रमान्प्रक्रमतो विष्णोरमिततेजसः। यदासीन्मङ्गलं राम तत्ते भवतु मङ्गलम्।।2.25.35।।
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राम O Rama, त्रीन् three, विक्रमान् strides, प्रक्रमतः of him who was occupying, अमिततेजसः highly lustrous, विष्णोः Visnu's, यत् मङ्गलम् whichever auspiciousness, आसीत् was to be, तत् मङ्गलानि that auspiciousness, ते भवतु may be yours.
O Rama by occupying three footsteps of space, highly lustrous Visnu owned the three worlds and obtained glory. May you obtain similar auspiciousness