Valmiki Ramayana Sundara Kanda Sarga 1 Shloka 169
Original Shlokaप्रविष्टोऽस्मि हि ते वक्त्रं दाक्षायणि नमोऽस्तु ते। गमिष्ये यत्र वैदेही सत्यं चासीद्वरस्तव।।5.1.169।।
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दाक्षायणि O dughter of Daksha, ते your, वक्त्रम् mouth, प्रविष्टः I have entered, अस्मि हि I am indeed, ते to you, नमः salutations, अस्तु may be, वैदेही Vaidhehi, यत्र wherever, गमिष्ये I will go, तव your, वरः च boon also, सत्यम् true, आसीत् was.
"O Dakshayani I have indeed entered your mouth and your boon has come true (as nobody can go against the boon of the Creator). Allow me to proceed in quest of Vaidhehi. My salutations to you."