The prayer to the Sacred Heart of Jesus is a Roman Catholic devotion. A devotion is something that people do or say to show their love for God and Jesus. Saint Margaret Mary Alacoque wrote the prayer. When Roman Catholics pray to the Sacred Heart of Jesus they are praying for a part of Jesus that they believe is divine. The devotion to the Sacred Heart of Jesus is also popular among some Anglo-Catholic Anglicans (Anglicans who use many of the same practices as Catholics).