What is a gratia gratis data?
On the Freely Given Graces that are in the School of Jesus Christ
The vessels of Thine election, O Lord, who bear Thy name and have been made fit to manifest Thine infinite goodness, wisdom, and mercy, are adorned by Thee with diverse freely-given graces. These they use in a holy manner, with a wondrous increase of sanctifying grace, for the conversion of their neighbors, and the great praise of Thy sweetest Spouse, the Church.
Indeed, even to this day, to some Thou hast given a faith that is an extraordinary certainty of faith: so that they believe invisible things with such firmness and adherence that they are fit to confirm their brethren in the faith. To others is given the word of wisdom - that is, the highest knowledge of divine things - by which they are made powerful to wonderfully instruct others. To others is given the word of knowledge - that is, a wondrous understanding of human affections and affairs - through which they manifest the invisible. To others is given the grace of healings, as is evident from the miraculous cures that even now occur through the prayers or relics of Thy friends. To others is given the working of mighty wonders, ordained for the manifestation of Thy divine power, as can be seen from the lives of Thy saints whom Thou hast even in this age: in the raising of the dead, crossing of rivers, and other occasions where Thy majesty has been glorified. To others is given prophecy, so that they may know what Thou alone knowest, such as future contingent events; and in this, Thou hast had in these days many renowned servants who have foretold many things which the outcome has confirmed. To others is given the discernment of spirits, so that they may know the secrets of hearts and rightly discern by Thy light—in which there are many wondrous examples even now accomplished through Thy friends. To others are given kinds of tongues, by which they may speak with diverse nations - a grace once given to Thy school, though now, O Lord, I know not if it is still given. Yet perhaps in some event Thou dost bestow it upon certain chosen friends whom Thou dost send to nations that know Thee not, to evangelize the joy of Thy kingdom. To others is given the interpretation of speeches, so that with marvelous force and efficacy they may instruct, teach, delight, and move - which Thou dost daily prove, O Lord, in the Church through fitting ministers of the New Testament, which Thine infinite love hast made.
These are the graces which Thy Spirit freely distributes to each as He wills, for the good of their neighbors. Yet Thy disciples so use them, when moved by Thee, that they themselves first profit in Thy school. And though they prophesy and work many miracles, they do not vanish in their own thoughts but humble themselves, knowing that even sinners can work miracles in Thy name, so that no flesh may glory before Thee. Thus, in pure and humble hearts, Thy school works many virtues, so that Thou mayest be glorified in it. For it seeks in all things to sing of the infinite greatness of Thy goodness and mercy in this valley of tears, soon to ascend - after the weeping - to the choirs singing to Thee in the state of most blessed enjoyment and most lively life.