Both on the divine and on the human plane, the working of grace is more sublime and glorious than the working of miracles. God usually works miracles only in visible things, as when in a supernatural way, He restores health to a man or raises the dead to life. But by grace He works in the soul and, in a manner, creates the soul anew, elevates it above its nature, plants in it the germ of supernatural life. He reproduces Himself in it—so to speak—impressing upon it the image of His own nature.
Thus, the work of grace is the greatest wonder of God’s omnipotence. It is even greater than His creation of the world out of nothing. It can be compared only with that unspeakable act of God the Father by which He begets from all eternity His own Son, equal to Himself, and in time unites Him with a human nature. Supernatural, sublime, and full of mystery as is the generation of Christ, so supernatural and mysterious is the infusion of grace into our souls, because, in the words of St. Leo, we thereby participate in the generation of Christ. (Serm. 26, cap. 2.).
However, we must cooperate more in this work than the Saints could in the miracles worked through them by God. They could only suffer God to act through their mediation, without being able of their own power to contribute anything. But when grace is concerned, God wills that we ourselves, with His assistance, prepare our soul for it, receive it from His hand, preserve and cultivate it and merit its increase.
O wonderful greatness which God has given us, taking our soul to Himself as His spouse, that by the power received from Him she may produce in herself the image of God and become the child of God! O wonderful power which God has granted to His Church, to communicate His grace to her children by her teaching and her Sacraments! Can man desire anything greater? Can he cooperate in any greater work? Do you wish to perform a great and wonderful work, admirable not in the sight of foolish men but in the sight of the Angels of Heaven? Do you wish to be made a spectacle to the world and to the Angels? Behold, this is the greatest work: labor to acquire and to merit an increase of grace for yourself and your fellow creatures.