B16 today on Humanae Vitae

The spouses, in fact, having received the gift of love, are called to become in turn gift to one another without reservations. Only thus the acts proper and exclusive to the spouses are really acts of love that, while uniting them in one flesh, build a genuine personal communion. Hence, the logic of the totality of the gift configures conjugal love intrinsically and, thanks to the sacramental effusion of the Holy Spirit, becomes the means to realize in one's life a genuine conjugal charity.The possibility to create a new human life is included in the integral donation of the spouses. If, in fact, every form of love tends to spread the fullness of which it lives, conjugal love has its own form of communicating itself: the generation of children. Thus not only is it similar to, but it participates in the love of God, who wills to communicate himself by calling human persons to life. To exclude this communicative dimension through an action directed to prevent procreation means to deny the profound truth of spousal love, with which the divine gift is communicated: "If one does not wish to expose to the free will of men the mission to generate life, insurmountable limits must necessarily be recognized to the possibility of man's dominion over his own body and its functions; limits that no man, both private as well as invested with authority, can licitly infringe" ("Humanae Vitae," 17). This is the essential nucleus of the teaching that my venerated predecessor Paul VI addressed to spouses, and that the Servant of God John Paul II, in turn, reaffirmed on many occasions, illuminating its anthropological and moral foundation.

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