Valmiki Ramayana Sundara Kanda Sarga 58 Shloka 16
Original Shlokaरामस्य च मया साह्ये वर्तितव्यमरिन्दम।।5.58.16।। रामो धर्मभृतां श्रेष्ठो महेन्द्रसमविक्रमः।
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अरिन्दम subduer of enemies, मया by me, रामस्य Rama's, साह्ये received help, वर्तितव्यम् has to make efforts, महेन्द्रसमविक्रमः equal to Mahendra in valour, रामः Rama, धर्मभृताम् among the righteous, श्रेष्ठः foremost.
'O subduer of enemiesI must make efforts to help Rama the foremost among the righteous, for I have received help (from your father) who is equal to Indra in valour'.