Addressing more than 100,000 people, Pope Benedict tells the congregation to be true to their faith.
The faithful came from dozens of countries to hear the Pontiff speak.
In his homily, the 81 year old told believers that the "the power of love is stronger than the evil which threatens us".
The Pope is on a three day visit to France. On his arrival at Lourdes he prayed in the grotto where Bernadette Soubirous said the miracle appearance of the Madonna took place.
He also drank water from a spring that believers say has healing powers.
France is a secular society, where religion is considered a private affair. But since Benedict's arrival in the country his talks are urging people not to be afraid to live their faith in public.
