Pope Francis described his late predecessor, Pope Benedict XVI, as "noble" and "kind" on Saturday evening, speaking at Vespers Mass in St. Peter's Basilica, Vatican City.
Francis praised the Pope Emeritus, who died at the age of 95, for his work and his faith.
"With emotion, we remember a person so noble, so kind. And we feel in our hearts so much gratitude: gratitude to God for having given him to the Church and to the world, gratitude to him, for all the good he has done and above all for his testimony of faith and prayer, especially in these last years of his retired life," Pope Francis said.
Benedict XVI led the Catholic church for almost eight years, before becoming the first pontiff in 600 years to resign from the role in 2013.
Throughout the day, people reacted with sadness to the news of the passing of the Pope Emeritus.
"I was approaching the square to pay my last respects, even though I am not a great believer. But he was a great philosopher and a great pope," said one woman.
Remembrance services were held in Benedict's native Germany. Church bells sounded and flags were raised - including in his home town of Märktl, to the southeast of the country -- which Benedict had called his 'spiritual homeland.'