In his final Sunday address before his resignation, Pope Benedict XVI said he was following God's wishes and that he was not abandoning the Catholic Church.
Addressing tens of thousands of people in St Peter's Square, the pope also said he would continue to serve and love the Church by praying and meditating after he abdicates on 28 February.
Pope Benedict, 85, announced his resignation on 11 February, saying ill-health meant he could not continue. He said he was following God's wishes in deciding to abdicate.
"The Lord is calling me to climb the mountain - prayer is not an isolation from the world," he said.
"I am not abandoning the Church and shall continue to serve it in a manner more adapted to my age and strength," through prayer and meditation, he added.
Pope Benedict will hold his last public appearance in the square on Wednesday before he retires to a life of seclusion and prayer.
