Valmiki Ramayana Ayodhya Kanda Sarga 25 Shloka 32
Original Shlokaयन्मङ्गलं सहस्राक्षे सर्वदेवनमस्कृते। वृत्रनाशे समभवत्तत्ते भवतु मङ्गलम्।।2.25.32।।
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वृत्रनाशे at the time of slaying of Vritra, सर्वदेवनमस्कृते salutations bestowed by all gods, सहस्राक्षे on god of a thousand eyes (Indra), यत् whichever, मङ्गलम् blessings, समभवत् was bestowed, तत् मङ्गलम् that auspiciousness, ते भवतु may happen to you.
May the same blessings bestowed by all the gods on the thousandeyed Indra at the time of killing Vritra be with you