The Sacred Heart is a religious devotion to Jesus' physical heart as the representation of the divine love for humanity. This devotion is predominantly used in the Roman Catholic Church, and also in strains of the Anglican Church and some Lutheran Churches. It stresses the central Christian concept of loving and adoring Jesus. The origin of this devotion in its modern form is derived from a French Roman Catholic nun, Marguerite Marie Alacoque, who said she learned the devotion from Jesus in visions. Predecessors to the modern devotion existed to some extent in the Middle Ages in various mystical sects. In the Roman Catholic tradition, the Sacred Heart has been closely associated with Acts of Reparation to Jesus Christ. In his encyclical Miserentissimus Redemptor, Pope Pius XI stated: "the spirit of expiation or reparation has always had the first and foremost place in the worship given to the Most Sacred Heart of Jesus". Devotion to the Sacred Heart is sometimes seen in the Eastern Catholic Churches, where it remains a point of controversy and is seen as an example of liturgical latinisation. The Sacred Heart is often depicted in Christian art as a flaming heart shining with divine light, pierced by the lance-wound, surrounded by a crown of thorns, and bleeding. Sometimes the image is over Jesus' body with his wounded hands pointing at the heart. The wounds and crown of thorns allude to the manner of Jesus' death, while the fire represents the transformative power of love. The Feast of the Sacred Heart has been a Solemnity in the Roman Catholic liturgical calendar since 1856, and is celebrated 19 days after Pentecost. As Pentecost is always celebrated on Sunday, the Feast of the Sacred Heart always falls on a Friday. In 2009, it will be celebrated on June 19.