39 We address Our special greetings to the Catholic parents. Their rights and duties as educators, conferred on them by God, are at present the stake of a campaign pregnant with consequences. The Church cannot wait to deplore the devastation of its altars, the destruction of its temples, if an education, hostile to Christ, is to profane the temple of the child's soul consecrated by baptism, and extinguish the eternal light of the faith in Christ for the sake of counterfeit light alien to the Cross. Then the violation of temples is nigh, and it will be every one's duty to sever his responsibility from the opposite camp, and free his conscience from guilty cooperation with such corruption. The more the enemies attempt to disguise their designs, the more a distrustful vigilance will be needed, in the light of bitter experience. Religious lessons maintained for the sake of appearances, controlled by unauthorized men, within the frame of an educational system which systematically works against religion, do not justify a vote in favor of non-confessional schools. We know, dear Catholic parents, that your vote was not free, for a free and secret vote would have meant the triumph of the Catholic schools. Therefore, we shall never cease frankly to represent to the responsible authorities the iniquity of the pressure brought to bear on you and the duty of respecting the freedom of education. Yet do not forget this: none can free you from the responsibility God has placed on you over your children. None of your oppressors, who pretend to relieve you of your duties can answer for you to the eternal Judge, when he will ask: "Where are those I confided to you?" May every one of you be able to answer: "Of them whom thou hast given me, I have not lost any one" ( John xviii. 9).
Source: Mit Brennender Sorge (Vatican.va)