Is “the heart” still a relevant symbol of God’s love in today’s world? In this fourth encyclical of his pontificate, written during the 350th anniversary year of the first apparition of the Sacred Heart of Jesus to Saint Margaret Mary Alacoque, Pope Francis affirms the centrality of the Sacred Heart in the history, theology, devotion, and missionary activity of the Church. The pope reflects on the Christian meaning of “the heart” as the integrating center of the person. He then turns to Scripture, magisterial teaching, and the spirituality of the saints—including Francis de Sales, Claude de la Colombière, and Therese of Lisieux—to draw out the full significance of devotion to the Sacred Heart of Jesus. Pope Francis concludes by proposing an integral, mission-oriented devotion to the Sacred Heart as a Christian response to a world searching for love. Dilexit Nos is a stirring call to personal conversion, reparation, forgiveness, and social action informed by the love of Jesus for humanity.