"...husbands and wives should first of all recognize clearly the teaching of Humanae vitae as indicating the norm for the exercise of their sexuality, and that they should endeavor to establish the conditions necessary for observing that norm".
Pope John Paul II, Familiaris consortio
Contraception, along with divorce are the two main underpinnings of the culture of death. Divorce seeks to break unity, contraception perverts that unity. It is tragic to discover so many Catholics dissenting on these two issues. In essence, these people, without even knowing it, have succumbed to a form of gnostic "Christianity" that is a creation of their personal whims, rather than being a religion of submission to the will of the Creator as manifested through His Church. Dissent on contraception reflects a bitter hedonistic conception of sexuality. It further rejects Truth, and replaces it with revealed religion being reduced to an immanentist subjectivity. It is a crisis of Truth and Being that has created the moral/ethical crisis (c.f. An Introduction to Christianity, Ratzinger, J).
Pope John Paul II in Familiaris consortio provided the Church and the world with an overview of why Humanae vitae was prophetic teaching of the Church of Christ. The late Holy Father began by underscoring the unity of the bishops with the Supreme Pontiff:
Thus, in continuity with the living tradition of the ecclesial community throughout history, the recent Second Vatican Council and the magisterium of my predecessor Paul VI, expressed above all in the Encyclical Humanae vitae, have handed on to our times a truly prophetic proclamation, which reaffirms and reproposes with clarity the Church's teaching and norm, always old yet always new, regarding marriage and regarding the transmission of human life.
For this reason the Synod Fathers made the following declaration at their last assembly: "This Sacred Synod, gathered together with the Successor of Peter in the unity of faith, firmly holds what has been set forth in the Second Vatican Council (cf. Gaudium et spes, 50) and afterwards in the Encyclical Humanae vitae, particularly that love between husband and wife must be fully human, exclusive and open to new life (Humanae vitae, 11; cf. 9, 12)."
The Holy Father then went on to call on theologians to collaborate with the Magisterium to ensure that the People of God do not fall into error:
For this reason, together with the Synod Fathers I feel it is my duty to extend a pressing invitation to theologians, asking them to unite their efforts in order to collaborate with the hierarchical Magisterium...
A united effort by theologians in this regard, inspired by a convinced adherence to the Magisterium, which is the one authentic guide for the People of God, is particularly urgent for reasons that include the close link between Catholic teaching on this matter and the view of the human person that the Church proposes: doubt or error in the field of marriage or the family involves obscuring to a serious extent the integral truth about the human person, in a cultural situation that is already so often confused and contradictory...
The Holy Father then develops the Church's teachings:
In an Integral Vision of the Human Person and of His or Her Vocation
In the context of a culture which seriously distorts or entirely misinterprets the true meaning of human sexuality, because it separates it from its essential reference to the person, the Church more urgently feels how irreplaceable is her mission of presenting sexuality as a value and task of the whole person, created male and female in the image of God.
In this perspective the Second Vatican Council clearly affirmed that "when there is a question of harmonizing conjugal love with the responsible transmission of life, the moral aspect of any procedure does not depend solely on sincere intentions or on an evaluation of motives. It must be determined by objective standards. These, based on the nature of the human person and his or her acts, preserve the full sense of mutual self-giving and human procreation in the context of true love. Such a goal cannot be achieved unless the virtue of conjugal chastity is sincerely practiced."(85)
It is precisely by moving from "an integral vision of man and of his vocation, not only his natural and earthly, but also his supernatural and eternal vocation,"(87) that Paul VI affirmed that the teaching of the Church "is founded upon the inseparable connection, willed by God and unable to be broken by man on his own initiative, between the two meanings of the conjugal act: the unitive meaning and the procreative meaning."And he concluded by re-emphasizing that there must be excluded as intrinsically immoral "every action which, either in anticipation of the conjugal act, or in its accomplishment, or in the development of its natural consequences, proposes, whether as an end or as a means, to render procreation impossible."
When couples, by means of recourse to contraception, separate these two meanings that God the Creator has inscribed in the being of man and woman and in the dynamism of their sexual communion, they act as "arbiters" of the divine plan and they "manipulate" and degrade human sexuality-and with it themselves and their married partner-by altering its value of "total" self-giving. Thus the innate language that expresses the total reciprocal self-giving of husband and wife is overlaid, through contraception, by an objectively contradictory language, namely, that of not giving oneself totally to the other. This leads not only to a positive refusal to be open to life but also to a falsification of the inner truth of conjugal love, which is called upon to give itself in personal totality...
The Church as Teacher and Mother for Couples in Difficulty
In the field of conjugal morality the Church is Teacher and Mother and acts as such. As Teacher, she never tires of proclaiming the moral norm that must guide the responsible transmission of life. The Church is in no way the author or the arbiter of this norm. In obedience to the truth which is Christ, whose image is reflected in the nature and dignity of the human person, the Church interprets the moral norm and proposes it to all people of good will, without concealing its demands of radicalness and perfection.
As Mother, the Church is close to the many married couples who find themselves in difficulty over this important point of the moral life: she knows well their situation, which is often very arduous and at times truly tormented by difficulties of every kind, not only individual difficulties but social ones as well; she knows that many couples encounter difficulties not only in the concrete fulfillment of the moral norm but even in understanding its inherent values.
But it is one and the same Church that is both Teacher and Mother. And so the Church never ceases to exhort and encourage all to resolve whatever conjugal difficulties may arise without ever falsifying or compromising the truth: she is convinced that there can be no true contradiction between the divine law on transmitting life and that on fostering authentic married love.(91) Accordingly, the concrete pedagogy of the Church must always remain linked with her doctrine and never be separated from it. With the same conviction as my predecessor, I therefore repeat: "To diminish in no way the saving teaching of Christ constitutes an eminent form of charity for souls."...
The Moral Progress of Married People
It is always very important to have a right notion of the moral order, its values and its norms; and the importance is all the greater when the difficulties in the way of respecting them become more numerous and serious.
Since the moral order reveals and sets forth the plan of God the Creator, for this very reason it cannot be something that harms man, something impersonal. On the contrary, by responding to the deepest demands of the human being created by God, it places itself at the service of that person's full humanity with the delicate and binding love whereby God Himself inspires, sustains and guides every creature towards its happiness.
But man, who has been called to live God's wise and loving design in a responsible manner, is an historical being who day by day builds himself up through his many free decisions; and so he knows, loves and accomplishes moral good by stages of growth.
Married people too are called upon to progress unceasingly in their moral life, with the support of a sincere and active desire to gain ever better knowledge of the values enshrined in and fostered by the law of God. They must also be supported by an upright and generous willingness to embody these values in their concrete decisions. They cannot however look on the law as merely an ideal to be achieved in the future: they must consider it as a command of Christ the Lord to overcome difficulties with constancy. "And so what is known as 'the law of gradualness' or step-by-step advance cannot be identified with 'gradualness of the law,' as if there were different degrees or forms of precept in God's law for different individuals and situations. In God's plan, all husbands and wives are called in marriage to holiness, and this lofty vocation is fulfilled to the extent that the human person is able to respond to God's command with serene confidence in God's grace and in his or her own will."