Valmiki Ramayana Yuddha Kanda Sarga 119 Shloka 9
Original Shlokaमदधीनंतुयत्तन्मेहृदयंत्वयिवर्तते । पराधीनेषुगात्रेषुकिंकरिष्याम्यनीश्वरी ।।6.119.9।।
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यत् that which, मदधीनम् mind under my control, तत् that, मे is my, हृदयंतु heart, त्वयि you, वर्तते abides, पराधीनेषु at others' mercy, गात्रेषु limbs, अनीश्वरी not possible, किम् what, करिष्यामि can I do
"That mind which is under my control is my heart and it abides in you. What can I do about my limbs when I am at others' mercy?"