Valmiki Ramayana Bala Kanda Sarga 44 Shloka 13
Original Shlokaयच्च गङ्गावतरणं त्वया कृतमरिन्दम। अनेन च भवान् प्राप्तो धर्मस्यायतनं महत्।।1.44.13।।
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अरिन्दम O Destroyer of enemies, त्वया by you, यत् since, गङ्गावतरणम् descent of Ganga, कृतम् has been materialised, अनेन by this, भवान् you, धर्मस्य of dharma, महत् great, आयतनम् sacred place, प्राप्त: have obtained.
O Destroyer of enemies by bringing about the descent of Ganga, you have secured a great abode in dharma.