"12. Do not admit anyone to the clergy, entrust to no one the ministry of the mysteries of God, allow no one to hear confessions or preach sermons, do not transfer any administration or office to anyone, before you carefully weigh, examine and "test their spirit to see if they are of God.""
"13. Would that We had not learned by experience how many "false apostles" the present age has spawned! These are "deceitful workmen who transform themselves into apostles of Christ." Unless we are on our guard "they will destroy the understanding of the faithful as the serpent seduced Eve by his cleverness, and they will fall away from their simplicity which is in Christ."[II Cor. 11] While you must care for the whole flock over which the Holy Spirit has placed you as bishop, the watchfulness, eagerness, and effort of your fatherly love and benevolence is demanded in particular by boys and young men. Christ by example and statement has particularly entrusted these to us [Mt 19, Mk 10, Lk 18.] and the enemies of private property and states who are striving to confound all laws, divine and human, hope to effect their wicked plans chiefly by corrupting their young minds. For they are aware that the young are like soft wax and can easily be drawn in any direction, bent and moulded and that they firmly retain a form once they have received it and it has been hardened by advancing years; then they will reject a different form. Hence the well-worn proverb from scripture: "A young man will not depart from his way even when he has grown old.''[Prov. 22]"
"14. Do not allow "that the children of this world be wiser in their generation than the children of light." Carefully investigate the directors given charge of boys and young men in seminaries and colleges, and the courses they are to follow, the teachers chosen for secondary schools, and the schools which are to be run. Keep out the ravening wolves who do not spare the flock of innocent lambs, and expel them if necessary by the way they entered. Eliminate them at once "according to the power which the Lord gave you for edification.'' [II Cor. 13] We must use to the full this power to eradicate this very serious threat to our children. This course is required for the safety of Church, state, leaders, and all human beings; their safety should be dearer and more important to Us than Our own life. Clement XIII treated this subject in his Brief to you on 25th November 1766."
Diu Satis, Nos. 12-14