The History of Mary’s Psalter
The history of the Rosary is bound up with the 150 Psalms of the Old Testament, otherwise known as the Psalter of David. From the dawn of Catholic history, monks and hermits prayed these Psalms as part of their daily liturgical life.
Saint Benedict, in his Holy Rule, explains that the monks of the desert recited the 150 Psalms every day. Saint Benedict arranged the Psalms for his monks so that all 150 would be recited in one week. This became the Divine Office (Breviary) that priests and religious recited every day until the post-Conciliar aggiornamento revolutionized both Breviary and Mass.
The story of Mary's Psalter reportedly begins with the Irish monks in the 7th Century. These monks divided the 150 Psalms of David into a Na tri coicat format of three groups of fifty. Arranged in such a way, the fifties served both as reflective and corporal/penitential prayer.
The people of the Middle Ages, in their great love of Our Lady, set to fashioning Rosariums in Her honor. They composed Psalms in praise of Mary to match the 150 Psalms of David. St. Anselm of Canterbury (1109) made such a Rosary. In the 13th Century, St. Bonaventure divided his 150 Marian Psalms into three groups. The first group commenced with the word Ave, the next with Salve, and the final fifty Psalms commenced with the word Gaude. Such Rosaries of praise took the name of Our Lady's Psalter.
It was not long before the custom of reciting Hail Mary's became the substitute of reciting the Psalms in praise of Our Lady. By the 13th Century, writes the Redemptorist Father James Galvin, the number of Aves was set at one hundred and fifty, to equal the number of the Psalms of David.
Saint Thomas Aquinas explains that the Psalter of David, composed as it is of one hundred and fifty Psalms, is divided into three equal parts of fifty Psalms each. These three equal parts represent, figuratively, the three stages in which the faithful find themselves: the state of penance, the state of justice, the state of glory. Likewise, explains Father Anthony Fuerst, the Rosary of Mary is divided into three parts of fifty Hail Mary's each, in order to express fully the phases of the life of the faithful: penance, justice and glory.
Heaven Itself declared the immeasurable value of this Psalter. In 1214, Our Blessed Mother told Saint Dominic to preach My Psalter in order to rekindle faith, to convert sinners and to crush stubborn heresy. Saint Louis de Montfort tells the story in his magnificent work, The Secret of The Rosary.
Saint Dominic, writes Saint Louis, seeing that the gravity of the peoples' sin was hindering the conversion of the Albigensians, withdrew to a forest near Toulouse where he prayed unceasingly for three days and three nights. During this time he did nothing but weep and do harsh penances in order to appease the anger of Almighty God. He used his discipline so much that his body was lacerated, and finally he fell into a coma.
Our Lady then appeared to him, accompanied by three angels. She said, Dear Dominic, do you know which weapon the Blessed Trinity wants to use to reform the world?
Saint Dominic asked Her to tell him. Our Lady responded:
I want you to know that, in this kind of warfare, the battering ram has always been the Angelic Psalter which is the foundation stone of the New Testament. Therefore, if you want to reach these hardened souls and win them over to God, preach My Psalter.
Our Lady's words contain two special points of interest:
1) She uses the language of the Church militant. She does not speak of the Rosary in a sentimental manner, in order to achieve good feelings or pan-religious unity. No, She refers to it as a battering ram against heresy.
2) She twice uses the term Psalter, which is the Rosary designated as 150 Aves that link it to the Psalms of David.
Regarding the Rosary's traditional structure, Msgr. George Shea writes, Because its 150 Hail Mary's correspond to the 150 Psalms of the Psalter, the complete Rosary is sometimes called Our Lady's Psalter. In fact, the latter was its common designation down to the end of the 15th Century, while Rosary’ was reserved for a part, i.e., a third, of Our Lady's Psalter.
As late as the last quarter of the 15th Century, Blessed Alaus de Rupe protested vigorously against the use of the terms Rosario, Chapelet or Corono, and insisted that the title of Our Lady's Psalter be retained. Msgr. Shea points out that the first indication from a Pope that the Psalter of Mary is commonly called Rosary is found in the Apostolic Constitution of Pope Leo X, Pastor Aeterni dated October 6, 1520, over three hundred years after Our Lady spoke to Saint Dominic.