Haurietis Aquas presents devotion to the Sacred Heart of Jesus as a gift that refreshes, strengthens, purifies, and forms the faithful in virtue. Drawing on biblical prophecy, the Pope relates the Heart to the new covenant in which God writes his law within human hearts, forgives sins, and gives the Holy Spirit as living water. Christ’s Heart signifies divine charity joined to his complete human nature: by assuming humanity while remaining God, Jesus redeems and sanctifies the whole person.

The devotion is described as a high act of religion requiring consecration, thanksgiving, adoration, and love in response to Christ’s wounded body and self-giving sacrifice. The Eucharist, the Mass, and the priesthood flow from this love and continue to provide for the Church’s spiritual life. Following Mary, the Apostles, and the Fathers, believers unite inward affection with outward service, loving God with the whole person. The encyclical notes the devotion’s widespread growth and spiritual fruits, echoes Pope Leo XIII’s teaching on the Heart as a sign of divine favor and light, and concludes by blessing those who promote it.