Valmiki Ramayana Sundara Kanda Sarga 37 Shloka 57
Original Shlokaआरम्भस्तु मदर्थोऽयं ततस्तव निरर्थकः। त्वया हि सह रामस्य महानागमने गुणः।।5.37.57।।
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ततः then, मदर्थः for my sake, तव your, आरम्भस्तु effort, निरर्थकः futile, त्वया सह along with you, रामस्य Rama, आगमने coming here, महान् great, गुणः merit.
"All your effort for my sake would be futile. Hence Rama's arrival along with you will be of great benefit.