First Sunday in October or October 7th
Lessons iv -vi From Matins of the Feast
When the wicked heresy of the Albigensians was growing in the district of Toulouse, and striking deeper roots day by day, St. Dominic, who had just laid the foundations of the Order of Preachers, threw himself wholeheartedly into the task of destroying the heresy. That he might be the better able to overcome it, he implored with earnest prayers the aid of the Blessed Virgin, whose dignity these errors shamelessly attacked, and to whom it is given to destroy all heresies throughout the world. As everyone knows, she instructed Dominic to preach the Rosary to the people as a unique safeguard against heresy and vice, and he carried out this commission with a wonderful ardor of soul, and with great success. The Rosary is a form of prayer in which we recite fifteen decades of the Angelic Salutation, with the Lord's Prayer between decades. During each decade we recall in devote meditation one of the mysteries of our redemption. From that time, then, St. Dominic began to promulgate and promote in a wonderful way this pious method of praying. His role in the propagation of the Rosary has been mentioned in the writings of many of the popes.
From this salutary practice countless fruits have flowed to Christendom. Among these, we should especially mention the victory over the powerful tyranny of the Turks, won at the battle of Lepanto by Pope St. Pius V, and the Christian princes he had aroused. For, as this victory was won on the very day on which the sodality of the most holy Rosary throughout the world had been offering their accustomed supplications, and carrying out the prescribed prayers, it was rightly attributed to these prayers. Gregory XIII testified to this fact when he decreed that for such a unique benefit thanks should always be offered everywhere throughout the world to the Blessed Virgin under the title of the Rosary, and, in all churches where there is an altar consecrated under this title, the Divine Office should always be celebrated with the rite of a greater double. Other popes have granted almost innumerable indulgences to the recitation of the Rosary, and to Rosary societies.
Clement XI, noting the circumstances of the equally famous victory of Charles VI, the emperor elect, over the innumerable forces of the Turks in Hungary in the year 1716, held that this victory was to be attributed to the intercession of the Blessed Virgin Mary. This victory occurred on the feast of the Dedication of Our Lady of the Snow; and, at almost the time of the battle, the Confraternity of the Most Holy Rosary was offering a public and solemn supplication in the city of Rome, with a great crowd of people pouring out fervent prayers to God with great devotion for the overthrow of the Turks, and humbly imploring the powerful aid of the Mother of God to help the Christians. Looking also with the eyes of faith at the raising of the Turks siege of the island of Corcyra shortly afterwards, he held that this victory too must be ascribed to the patronage of the Blessed Virgin. To keep alive, therefore, the memory of these great benefits, and to assure a perpetual thanksgiving for them, Clement extended the feast of the Most Holy Rosary, still with the rite of a greater double, to the universal Church. Benedict XIII decreed that all these things be written into the Roman Breviary. In a most difficult period for the Church, when the raging flood of evils seemed overwhelming, Leo XIII in repeated encyclicals strongly urged all the faithful throughout the world to recite the Rosary; especially during the month of October. He raised the rank of the feast, and added to the Litany of Loretto the invocation "Queen of the Most Holy Rosary." He also granted a special Office, to be recited by the universal Church on this feast. We should continue, therefore, to honor the Most Holy Mother of God by this devotion which is so pleasing to her; so that she, who has so often answered Christ's faithful when they prayed the Rosary and brought their earthly enemies to defeat and destruction, may in the same way give us victory over the powers of hell.