Pope Leo has urged the Catholic Church to admit its own failings and heal "deep wounds" inflicted within its ranks.
The Pope will spend time in Lourdes near a famed Catholic mosaic shrine, built by Reverend Marko Rupnik who has been accused of sexual abuse.
Addressing crowds of more than 150,000 in Lourdes, the Pope said the Church must have the courage to face its past, but did not directly reference abuse scandals in France that sparked nationwide shock.
Arriving in Paris on Friday, the Pope went to Lourdes on Saturday and will visit Metz in the north-east on Monday.
During the trip, he has again urged the world to reconsider the development of artificial intelligence and drew 800,000 people for an outdoor Mass on the Champs-Élysées in Paris.
Local leaders are hoping he will help repair the Church's standing after a 2021 report found that some 330,000 French children had been abused by Catholic clergy and lay leaders over seven decades.
The Vatican provided a statement of what Pope Leo had mentioned in an earlier, closed-door meeting with French bishops on Sunday.
The Pope is due to have a closed-door meeting with seven French victims of abuse by clergy later on Sunday.
Some survivors said they were doubtful the encounter would result in quick changes by the Church.
"I am quite sceptical that the pope will solve the issue, at least not immediately," said Michèle Le Reun-Gaigné, co-president of an association for survivors in western France.