Valmiki Ramayana Aranya Kanda Sarga 6 Shloka 8
Original Shlokaत्वमिक्ष्वाकुकुलस्यास्य पृथिव्याश्च महारथ। प्रधानश्चासि नाथश्च देवानां मघवानिव।।3.6.8।।
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महारथ O great charioteer, त्वम् you, अस्य of this, इक्ष्वाकुकुलस्य of the line of the Ikshvakus, पृथिव्याश्च of this earth, देवानाम् of gods, मघवानिव like Indra, प्रधानश्च chief also, नाथश्च lord as well
O great charioteer you are the lord of the Ikshvaku race and of the world just like Indra, chief among the gods.