Valmiki Ramayana Ayodhya Kanda Sarga 25 Shloka 24
Original Shlokaअग्निर्वायुस्तथा धूमो मन्त्राश्चर्षिमुखाच्च्युताः। उपस्पर्शनकाले तु पान्तु त्वां रघुनन्दन।।2.25.24।।
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रघुनन्दन O Joy of the Raghus O Son of the Raghu race, उपस्पर्शनकाले at the time of taking bath, त्वाम् you, अग्नि: fire, वायुः wind, तथा also, धूमः smoke, ऋषिमुखात् from the mouths of rishis, च्युताः released, मन्त्राश्च mantras, पान्तु protect you.
May Fire, Wind, Smoke and Mantras emanated from the mouths of rishis protect you when you take your ablutions, O Son of the Raghu race O Joy of the Raghus