This feast was instituted by Pope St. Pius V in thanksgiving for the great naval victory over the Turks at the battle of Lepanto on this day in the year 1570, a favor due to the recitation of the Rosary. This victory saved Europe from being overrun by the forces of Islam.
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The purpose of the rosary is to help us meditate on the great mysteries of our salvation. Pius XII called it a compendium of the gospel. The main focus is on Jesus—his birth, life, death and resurrection. The Our Fathers remind us that Jesus' Father is the initiator of salvation. The Hail Marys remind us to join with Mary in contemplating these mysteries. They also make us aware that Mary was and is intimately joined with her Son in all the mysteries of his earthly and heavenly existence. The Glorys remind us that the purpose of all life is the glory of the Trinity.
The rosary appeals to many. It is simple. The constant repetition of words helps create an atmosphere in which to contemplate the mysteries of God. We sense that Jesus and Mary are with us in the joys and sorrows of life. We grow in hope that God will bring us to share in the glory of Jesus and Mary forever.