sītā-kṛtāni vyasanānīśvarasya

martya-as a human being; avatarah-whose incarnation; tu-however; iha-in the material world; martya-siksanam-for teaching all the living entities, especially human beings; raksah-vadhaya-to kill the demon Ravana; eva-certainly; na-not; kevalam-only; vibhoh-of the Supreme Personality of Godhead; kutah-from where; anyatha-otherwise; syat-there would be; ramatah-of one enjoying; sve-in Himself; atmanah-the spiritual identity of the universe; sita-of the wife of Lord Ramacandra; krtani-appearing due to the separation; vyasanani-all the miseries; isvarasya-of the Supreme Personality of Godhead.