On December 10, 1925, Our Lady promised Sister Lucia that she would "...assist at the hour of death, with the graces necessary for salvation, all those who on the first Saturdays of five consecutive months confess, receive Holy Communion, pray a Rosary, and keep me company for a quarter of an hour meditating on the fifteen mysteries with the intention of offering me reparation."
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With the intention of making reparation for offenses committed against The Immaculate Heart of Mary: 1. Go to Confession 2. Receive Holy Communion. 3. Say five decades of the Holy Rosary 4. Meditate for 15 minutes on the mysteries of the Holy Rosary. (This is separate from saying the Rosary.)