Valmiki Ramayana Sundara Kanda Sarga 16 Shloka 4
Original Shlokaरामस्य व्यवसायज्ञा लक्ष्मणस्य च धीमतः। नात्यर्थं क्षुभ्यते देवी गङ्गेव जलदागमे।।5.16.4।।
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रामस्य Rama's, धीमतः prowess, लक्ष्मणस्य च and Lakshmana's, व्यवसायज्ञा might, देवी queen, जलदागमे by seeing the clouds, गङ्गेव like Ganga, अत्यर्थम् exceedingly, न क्षुभ्यते is not agitated.
"Just as river Ganga is not agitated by the rainbearing clouds, this Sita is not perturbed as she is aware of the prowess of Rama and might of Lakshmana.