Pope Francis has received applause as he paid tribute to his predecessor Benedict XVI during his homily, given in Italian, in front of the audience at St Peter's Square.
He sent Benedict XVI "prayers, affection and thanks".
Marking the feast of St Joseph today, Pope Francis said Christians must listen to God to "protect Christ in our lives so we can protect others".
Pope Francis has promised to bring his followers hope by service at his inauguration in front of a crowd of 150,000 in Rome.
Pope Francis will greet crowds before being inaugurated, a guide to the event at the Vatican today.