St. Margaret Mary Alacoque, a soul chosen by Our Lord, became the Apostle of His Sacred Heart to the world. This book offers a compelling and factual account of her life, from a childhood marked by hardship and abuse, endured with a gentle and forgiving spirit, to her profound mystical experiences as a religious. Readers will learn of her unwavering devotion, her visions of Christ at Paray Le Monial, and the divine guidance she received, unveiling the burning love of Jesus for His children. Like her Divine Spouse, she embraced suffering and penance, leading to the remarkable circumstances surrounding the revelation of the Sacred Heart devotion we cherish today. This biography explores her path from novice to mentor, the miracles that confirmed her mission, and her tireless efforts to promote this vital devotion – a devotion rooted in her acceptance of the cross. Experience the life and holiness of this remarkable saint and the enduring legacy of her work in the widespread veneration of the Sacred Heart that continues to this day.