61 Sometimes, it is true, and even in modern times, Our Lord makes the world, as it were, His plaything; for He has been pleased to elect to the priestly state men almost devoid of that learning of which We have been speaking; and through them He has worked wonders. But He did this that all might learn, if there be a choice, to prize holiness more than learning; not to place more trust in human than in divine means. He did this because the world has need, from time to time, to hear repeated that wholesome, practical lesson: "The foolish things of the world hath God chosen to confound the wise . . . that no flesh should glory in His sight."
Source: Ad Catholici Sacerdotii (Vatican.va)