Long ago, during a time of spiritual darkness and division, Saint Dominic devoted his life to converting sinners and bringing souls back to God. But his mission was not an easy one. Heresies were spreading, and hearts had grown cold. He prayed constantly for guidance and strength. According to the writings of Carthagena, Blessed Alan de la Roche shared that on many occasions, both our Lord and the Blessed Virgin Mary appeared to Saint Dominic, urging him to preach the Rosary more and more. They made it clear: the Rosary was not just a prayer, but a powerful weapon to combat sin and soften hardened hearts.

In one particular vision, as Blessed Alan recounted, the Blessed Virgin Mary had just appeared to Saint Dominic when suddenly, her Son, Jesus Christ, also appeared before him. With great love and approval, Jesus said to Dominic, “I rejoice to see that you do not rely on your own wisdom, and that you are not seeking the praise of men. Instead, with humility, you labor for the salvation of souls.” But Jesus also warned Dominic of a common mistake. “Many priests,” He said, “begin their preaching with fierce condemnations of sin, forgetting that a sick soul, like a sick body, must be gently prepared before it can accept strong medicine. Before anything else, people must be drawn into a spirit of prayer.” Jesus continued, “That is why I want you—and all priests—to first awaken a love of prayer in the hearts of the faithful, especially a love for my Angelic Psalter—the Rosary. If only people would begin to say it sincerely and persevere, God in His mercy could hardly refuse them His grace.”

And so, with Heaven’s blessing and guidance, Saint Dominic went forth with renewed purpose—not just to preach against sin, but to lead souls to the healing power of prayer, beginning with the Rosary. From that moment on, he became the great apostle of the Rosary, planting the seeds of devotion that would transform countless hearts for generations to come.
Source: Secrets of the Rosary