Valmiki Ramayana Ayodhya Kanda Sarga 21 Shloka 61

देवि O mother, सा such you, वनम् to the forest, व्रजन्तम् departing, मा me, अनुमन्यस्व allow, सत्येन by the strength of truth, ययातिः Yayati, यथा just like, पुनः again, समाप्ते after completion of the term, यथा as, पुनः again, अव्रजेयम् I shall come back, स्वस्त्ययनानि ceremonies causing prosperity, कुरुष्व you may perform.

Grant me permission O mother, to depart for the forest. Bless me and perform ceremonies for my wellbeing so that I shall return (to the city) after completion (of my exile) like Yayati (who came back to heaven) with the strength of truth.