Zoë Labouré was the daughter of a farmer at Fain-les-Moutiers in France, where she was born in 1806. She was the only one of a large family not to go to school and did not learn to read and write. Her mother died when she was eight, and when her elder sister, Louisa, left home to become a Sister of Charity, the duties of housekeeper and helper to her father fell upon her. When her mother died she chose the Blessed Virgin fro her mother, and when she was about 14 or so she heard a call to the religious life. After some opposition from her father, she was allowed to join the Sisters of Charity of St Vincent de Paul at Châtillon-sur-Seine in 1830.
She took the name Catherine, and after her postulance was sent to the order's convent in Rue du Bac in Paris, where she arived four days before the removal of the relics of St Vincent de Paul from Notre Dame to the Lazarist Church in Rue de Sèvres. On the day of those festivities, a series of visions began which were to make the name of Catherine Labouré famous. On many occasions during Mass, Catherine beheld Our Lord in front of the Blessed Sacrament and on other occasions she saw symbolic visions of St Vincent above the reliquary containing his incorrupt heart.
The first of the three principal visions took place three months later. On the night of 18 July, when at about 11:30 pm she was woken up suddenly by the appearance of a "shining child", who led her down to the sister's chapel. There Our Lady appeared and talked with her for over two hours, telling her that she would have to undertake a difficult task.
On 27 November, the same year, Our Lady appeared to Sister Catherine in the same chapel, in the form of a picture and as it were standing on a globe with shafts of light streaming from Our Lady's hands. Catherine described the event:
"I saw the Blessed Virgin standing on a globe, Her face was beautiful beyond words. Rays of dazzling light were streaming from gems on Her fingers, down to the globe. And I heard a voice say: 'Behold the symbol of graces which I will shower down on all who ask Me for them!' Then, an oval frame surrounded Our Lady on which I read the prayer, in letters of gold: 'O Mary, conceived without sin, pray for us who have recourse to Thee!' The oval frame turned and I could see, on the reverse side, enclosed in a frame of twelve stars, the letter M surmounted by a cross with a bar beneath. Below these symbols were the Hearts of Jesus and Mary, one surrounded by a crown of thorns, the other pierced by a sword. I heard a voice, which said to me: 'Have a medal struck according to this model. Those who wear it, when it is blessed, will receive great graces, especially if they wear it around their necks. There will be graces in abundance for all who wear it with confidence."
Sister Catherine confided in her confessor, Père Aladel, and he, after making very careful investigations, was given permission by the Archbishop of Paris, Monseigneur de Quelen, to have the medal struck. In June, 1832, the first 1,500 were issued. The Faith was encountering difficulties in France at this time and its revival has been attributed to this medal. So many conversions and physical cures were attributed to the medal that the name "Miraculous Medal" was given it by popular acclaim.
The Archbishop of Paris instituted a canonical inquiry into the alleged visions in 1836, before which, however, Sister Catherine could not be induced to appear. Further inquiries took place and eventually the tribunal decided in favour of the authenticity of the visions, taking into consideration the circumstances, the character of the sister concerned, and the prudence and level-headedness of Père Aladel. Until her death on 31 December 1876, Catherine lived unobtrusively among the community at Enghien-Reuilly caring for the sick, the aged and the infirm. Although the other sisters were aware that the one in their midst was the celebrated visionary of the Miraculous Medal, the identity was not made known until Catherine was on her death bed. Her funeral was the occasion of an outburst of popular veneration, and a child of 12, crippled from birth, was instantaneously cured at her grave soon after. Sister Catherine's body had been placed in a triple coffin and buried in a crypt in the chapel at 77, rue de Reuilly where it remained for over 50 years.
Following the announcement of her beatification the coffin was opened and the customary recognition of the relics took place, and it was then discovered that the remains were found to be perfectly intact and incorrupt. The hands and the face were of a pinkish colour slightly tinged, but intact. The following day the face had slightly darkened on account of its first contact with the air. After a cursory examination, the body was borne in solemn processeion to the motherhouse. The body was later placed in the motherhouse chapel under the side altar of Our Lady of the Sun, where it still reposes behind a covering of glass, allowing it to be viewed by the many visitors to the chapel.
Saint Catherine was canonized on 27 July 1947 and her feast day is observed on 28 November, the day after the feast of the Miraculous Medal.
(It is said that Cardinal Newman began wearing the medal two months before his conversion)