Valmiki Ramayana Yuddha Kanda Sarga 119 Shloka 25
Original Shlokaयथामेहृदयंनित्यंनापसर्पतिराघवात् । तथालोकस्यसाक्षीमांसर्वतःपातुपावकः ।।6.119.25।।
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मे my, हृदयम् mind, राघवात् at Raghava, नापसर्पतियथा never slid at all, तथा so also, लोकस्य world's, साक्षी witness, पावकः fire god, माम् me, सर्वतःalways, पातु protect me
"If it is true that my heart has never slid from Raghava at all, may the fire god protect me always and so also the world witness."