Valmiki Ramayana Yuddha Kanda Sarga 120 Shloka 20
Original Shlokaत्वम्यज्ञस्त्वंवषटकारस्त्वमोङ्कारःपरात्परः ।।6.120.20।। प्रभवंनिधनंवातेनोविदुःकोभवानिति ।
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त्वम् you are, यज्ञः sacrificial ritual, त्वम् you are, वषटकारः Vasat, त्वम् you are, ओङ्कारः syllable OM, परात् higher, परः highest, ते you, प्रभवम् origin, निधनंचापि nor end, नोविदुः not know, भवान् you, कःइति who you are
"You are the form of sacrifice ritual you are worshipped by Vasat. You are the syllable OM. Only the highest of the higher know you. You are without a beginning or end. Who you are is not known to Vedas also?"