2 The cause which now moves Us to raise Our voice is of very serious importance. It demands all the attention of your mind and all the energy of your pastoral office to counteract the disorder which has already produced the most destructive effects. If this disorder is not radically removed with a firm hand, even more fatal consequences will be felt in the coming years. In fact, Venerable Brethren, We have letters, full of sadness and tears, from several of you, in which you deplore the spirit of insubordination and independence displayed here and there among the clergy. Most assuredly, a poisonous atmosphere corrupts men's minds to a great extent today, and the deadly effects are those which the Apostolic Saint Jude formerly described: "These men also defile the flesh, disregard authority, deride majesty." That is to say, over and above the most degrading corruption of manners there is also an open contempt for authority and for those who exercise it. What overwhelms Us with grief, however, is the fact that this spirit should creep into the sanctuary even in the least degree, infecting those to whom the words of Ecclesiasticus should most fittingly be applied: "Their generation, obedience and love." This unfortunate spirit is doing the damage especially among young priests, spreading among them new and reprehensible theories concerning the very nature of obedience. In order to recruit new members for this growing troop of rebels, what is even more serious is the fact that such maxims are being more or less secretly propagated among youths preparing for the priesthood within the enclosure of the seminaries.
Source: Pieni L'Animo (Vatican.va)