St. Margaret Mary Alacoque is one of the most extraordinary visionaries in the history of the Church. As the apostle of devotion to the Sacred Heart, her visions not only have full validation as authentic in virtue of their papal approval and her canonization, but have also experienced universal adoption in the Church with the promulgation of the Feast of the Sacred Heart of Jesus and widespread promotion of the First Fridays devotional practice, as well as the Thursday night Holy Hour.

Devout from youth, St. Margaret Mary vowed at a young age to become a nun, but she delayed until she was 24 and could no longer withhold herself from Christ. She suffered much in her life, but she was gifted with visions of Our Lord, visions which became the basis of her promotion of the Sacred Heart devotion. In addition to the harsh (and at times seemingly excessive) penances she placed on herself, she received opprobrium from her sisters, who doubted the authenticity of her visions and mission, and much opposition from others in the Church, too. Through it all, her mission from the Lord’s Sacred Heart triumphed, and she became the ultimate advocate of the furnace of Divine Charity beating for souls in Our Lord’s breast.

After her death, Fr. John Croiset, S.J., one of Margaret Mary’s confessors and directors, compiled in 1691 the revelations and prayers she had had relevant to the devotion to the Sacred Heart. Unfortunately, Fr. Croiset had made some procedural errors in the eyes of the Church, and so his book was forbidden and forgotten for about two hundred years. However, it was discovered again and saw new life.

For anyone who wishes to know more about the Sacred Heart of Jesus and how to adore It, Devotion to the Sacred Heart is the original guide to one of the tenderest and most exceedingly precious devotions in the Church’s arsenal. All treasures of graces, truth, beauty, goodness, joy, and love are contained in the Lord’s Heart. May we approach It with the zeal and humility of St. Margaret Mary and Fr. Croiset to serve Our Lord most intimately.