lankam ayus ca kalpantam
yayau cirna-vratah purim
aropya—keeping or placing; aruruhe—got up; yanam—on the airplane; bhratrbhyam—with His brother Laksmana and the commander Sugriva; hanumat-yutah—accompanied by Hanuman; vibhisanaya—unto Vibhisana, the brother of Ravana; bhagavan—the Lord; dattva—gave charge; raksah-gana-isatam—the power to rule over the Raksasa population of Lanka; lankam—the state of Lanka; ayuh ca—and the duration of life; kalpa-antam—for many, many years, until the end of one kalpa; yayau—returned home; cirna-vratah—finishing the duration of time living in the forest; purim—to Ayodhya-puri.
After giving Vibhisana the power to rule the Raksasa population of Lanka for the duration of one kalpa, Lord Ramacandra, the Supreme Personality of Godhead [Bhagavan], placed Sitadevi on an airplane decorated with flowers and then got on the plane Himself. The period for His living in the forest having ended, the Lord returned to Ayodhya, accompanied by Hanuman, Sugriva and His brother Laksmana.
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