Devotion to the Sacred Heart, as we know it, began about the year 1672. On repeated occasions, Jesus appeared to Saint Margaret Mary Alacoque, a Visitation nun, in France, and during these apparitions He explained to her the devotion to His Sacred Heart as He wanted people to practice it. he asked to be honored in the symbol of His Heart of flesh; he asked for acts of reparation, for frequent Communion, Communion on the First Friday of the month, and the keeping of the Holy Hour. - EWTN