The Rosary reached its widest انتشار in the 15th century thanks to the Dominican Alan de la Roche. He calls this prayer the “Psalter of the Virgin” and composes it with 150 Hail Marys (just as there are 150 psalms in the Bible), divided into decades and interspersed with the Our Father. He also defines the themes of the Gospel meditations that today correspond to the Joyful, Sorrowful, and Glorious Mysteries. We must await the intervention of Saint John Paul II to have the Luminous Mysteries. This way of praying had already been in use for some time, but he deserves credit for defining it precisely in order to spread devotion to the Virgin Mary. 

The promises to Blessed Alan

Blessed Alan writes in his memoirs that he received 15 promises directly from the Virgin connected with praying the Rosary:
1. Whoever serves me constantly by praying my Rosary will receive special graces.
2. To all those who devoutly pray my Rosary, I promise my very special protection and great graces.
3. The Rosary will be a most powerful weapon against Hell; it will destroy vices, dispel sin, and overthrow heresies.
4. It will cause virtues and holy works to flourish again, obtain abundant mercies from God for the faithful, and draw people's hearts away from love of the world and its vanities toward love of God, raising them to desire eternal things. How many souls will be saved through this means!

5. The soul that commends itself to me through my Rosary will not perish.
6. Whoever devoutly prays the Holy Rosary while meditating on the mysteries will not be abandoned by the Lord: they will not die suddenly while in God's disfavour; rather, if they are sinners, they will convert, and if they are righteous, they will remain in grace, and they will be made worthy of eternal life.
7. The true devotees of my Rosary will not die without the sacraments.
8. I desire that those who pray my Rosary may have the light and fullness of grace in life, and at death be admitted to share in the merits of the blessed in Paradise.
9. Every day, I free souls devoted to the Rosary from Purgatory.
10. The true children of my Rosary will enjoy great glory in heaven.
11. Whatever you ask for through it, you will obtain.
12. Those who spread the Rosary will be helped by me in all their needs.
13. I have obtained from my Son that all supporters of the Rosary may have the entire heavenly court as their intercessors in life and at the hour of death.
14. Those who pray my Rosary are my children and brothers and sisters of Jesus Christ.
15. Devotion to my Rosary is a great sign of predestination. 

These promises, although expressed in language that may seem somewhat distant to us, show us how dear the Rosary is to the Virgin Mary and how much good it can do for our lives and the lives of all those for whom we pray.
One more reason to love it, pray it, spread it, and let it transform you!