In February 1858, the Blessed Virgin Mary appeared 18 times to a girl of 14 named Bernadette Soubirous (Saint Bernadette – canonized in 1933) in a natural grotto at Massabielle. While Bernadette could see her, others could not. The Lady named herself during the 17th apparition.
During the 9th apparition, the Lady told Bernadette to drink from a spring of water under a rock, though there was no spring there previously. So, Bernadette began to dig and a small pool developed. The spring began to flow after another day. The water of the spring seems to be the "catalyst" for miraculous cures of maladies. Since the apparitions occurred several dozen inexplicable cures have been effected at Lourdes, which after serious investigation have been considered miraculous by the Church.
The content of the Blessed Virgin’s message in the apparition focused on the need for prayer and penance. During the 13th apparition of 2 March the Lady said "Please go to the priests and tell them that a chapel is to be built here. Let processions come hither." The parish priest would do nothing until the Lady identified herself. During the 16th long apparition of 25 March 1858 Bernadette was holding a lighted candle. When the candle burned all the way down to her hand, Bernadette was not burned or hurt even though the flame was in contact with her skin for over 15 minutes. During that same apparition Bernadette again asked the Lady her name but she just smiled back. Atter repeating the question three times, the Lady said in the local dialect, "I am the Immaculate Conception". Four years earlier, Bl. Pope Pius IX had promulgated the doctrine of the Immaculate Conception, something which Bernadette and most people of the area would have had no way of knowing.
Concede, misericors Deus,
fragilitatis nostrae praesidium,
ut, qui immaculatae Dei Genetricis memoriam agimus,
intercessionis eius auxilio,
a nostris iniquitatibus resurgamus.
Grant, O merciful God,
O assistance of our weakness,
that we who are keeping the memory of the Immaculate Mother of God,
may rise up again from our sins
by the help of her intercession.