Consequently, if the mission of generating life is not to be exposed to the arbitrary will of men, one must necessarily recognize unsurmountable limits to the possibility of man's domination over his own body and its functions; limits which no man, whether a private individual or one invested with authority, may licitly surpass. And such limits cannot be determined otherwise than by the respect due to the integrity of the human organism and its functions, according to the principles recalled earlier, and also according to the correct understanding of the "principle of totality" illustrated by our predecessor Pope Pius XII. (21) 

The Church, Guarantor of True Human Values

18. It can be foreseen that this teaching will perhaps not be easily received by all: Too numerous are those voices-amplified by the modern means of propaganda-which are contrary to the voice of the Church. To tell the truth, the Church is not surprised to be made, like her divine founder, a "sign of contradiction," (22) yet she does not because of this cease to proclaim with humble firmness the entire moral law, both natural and evangelical. Of such laws the Church was not the author, nor consequently can she be their arbiter; she is only their depositary and their interpreter, without ever being able to declare to be licit that which is not so by reason of its intimate an unchangeable opposition to the true good of man.

In defending conjugal morals in their integral wholeness, the Church knows that she contributes towards the establishment of a truly human civilization; she engages man not to abdicate from his own responsibility in order to rely on technical means; by that very fact she defends the dignity of man and wife. Faithful to both the teaching and the example of the Savior, she shows herself to be the sincere and disinterested friend of men, whom she wishes to help, even during their earthly sojourn, "to share as sons in the life of the living God, the Father of all men." (23)

III. Pastoral Directives

 The Church, Mater et Magistra

19. Our words would not be an adequate expression of the thought and solicitude of the Church, mother and teacher of all peoples, if, after having recalled men to the observance and respect of the divine law regarding matrimony, we did not strengthen them in the path of honest regulation of birth, even amid the difficult conditions which today afflict families and peoples. The Church, in fact, cannot have a different conduct towards men than that of the Redeemer. She knows their weaknesses, has compassion on the crowd, receives sinners; but she cannot renounce the teaching of the law which is, in reality, that law proper to a human life restored to its original truth and