In addition to the Miraculous Medal, the Virgin Mary chose to use St. Vincent de Paul's Daughters of Charity to reveal a second great sacramental: the Green Scapular.
Mary appeared to Sister Justine Bisqueyburu in Paris, France, on Jan. 28, 1840. Actually the fifth of a series of apparitions, Justine was given the design of a new scapular. Sr. Justine was hesitant at first, but eventually revealed the devotion to her Spiritual Director Fr. Aladel, who was also the director of St. Catherine Laboure of the Miraculous Medal.
After much delay, the scapulars were produced and distributed with many conversions and cures following.
The Green Scapular emphasized the theme of Mary's Immaculate Conception. Bl. Pope Pius IX twice strongly recommended its promotion and use.
Requirements
It is not necessary to wear the Green Scapular. It may be carried upon one's person, i.e., wallet, pocket, or kept in a designated location, i.e., one's bedroom.
To daily pray the words inscribed upon the Scapular: "Immaculate Heart of Mary, pray for us now and at the hour of our death."
No enrollment of any kind is necessary, but each scapular should be blessed by a priest.
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Green Scapular Devotion