Today Dominicans celebrate the Feast of our Co-Protectress, St. Catherine of Alexandria, Martyr. Saint Dominic received many heavenly visions of her and chose her with Mary Magdalene to be Protectress of the Dominican Order. Catherine is the patron of philosophers because of the wisdom and reasoning with which she spoke in defence of the faith.
Tradition has it that she appeared twice in visions during the early days of the Order, plus again in the 16th century. She was one of the Virgins along with St. Cecilia who accompanied the Blessed Virgin Mary when she gave Bl. Reginald the scapular. She also accompanied the Blessed Virgin in the vision in which St. Dominic saw the Virgin Mary sprinkling the brethren while they slept. Lastly, she again accompanied the Blessed Virgin, along with St. Mary Magdalene (co-patroness of the Order), in preparation for the painting of the miraculous image of St. Dominic in Soriano.

From the ''Vitae Fratrum''
“Once when St Dominic was passing the night in the church in prayer, about midnight he went out and entered the dormitory. After looking at his brethren he resumed his prayer at the entrance of the dormitory. While standing erect as he prayed, he chanced to glance to the other end of the dormitory and saw three very comely ladies advancing towards him, of whom the central figure seemed to be a lady more dignified and of higher rank than the others. One of the two attendants (St. Catherine of Alexandria) carried a beautiful and resplendent vessel of holy water, and the other (St. Cecilia) a sprinkler, which she presented to the third who walked between them. This one sprinkled the brethren and blessed them, but as she passed along doing so there was one friar whom she neither blessed nor sprinkled. St Dominic observed this attentively, and noting whom it was, followed the lady as far as the lamp which hung in the middle of the dormitory: there he threw himself at her feet and began earnestly to beg her to say who she was, although he knew very well all the while.
Now at that time the beautiful and devout anthem, the Salve Regina, was not sung in the convents of our brethren and sisters in Rome, but merely said kneeling. Then the lady addressed St Dominic and said: ‘I am she whom you greet every evening, and when you say “Turn then our Advocate,” I prostrate myself before my Son for the preservation of this Order.’ St Dominic then inquired who her companions might be, where unto she made answer: ‘One of them is Cecilia and the other Catherine.’ Upon this St Dominic made further inquiry touching the brother whom she had passed by, and why she had neither sprinkled nor blest him with the rest: at this she answered: ‘Simply because he was unworthy of it.’ Then she resumed sprinkling and blessing the remaining friars, and went away.”

Let us pray.
O God, you gave the law to Moses on the summit of Mount Sinai, and through your holy angels, wonderfully put in that same place the body of the blessed Catherine, your virgin and martyr; grant, we beseech you, that by her merits and intercession, we may reach that mountain which is Christ. Through Christ our Lord.