In fact, while the behavioural sciences, like all experimental sciences, develop an empirical and statistical concept of “normality”, faith teaches that this normality itself bears the traces of a fall from man’s original situation — in other words, it is affected by sin. Only Christian faith points out to man the way to return to “the beginning” (cf. Mt 19:8), a way which is often quite different from that of empirical normality. Hence the behavioural sciences, despite the great value of the information which they provide, cannot be considered decisive indications of moral norms. It is the Gospel which reveals the full truth about man and his moral journey, and thus enlightens and admonishes sinners; it proclaims to them God’s mercy, which is constantly at work to preserve them both from despair at their inability fully to know and keep God’s law and from the presumption that they can be saved without merit. God also reminds sinners of the joy of forgiveness, which alone grants the strength to see in the moral law a liberating truth, a grace-filled source of hope, a path of life. — from Veritas Splendor (1993)
The service which moral theologians are called to provide at the present time is of the utmost importance, not only for the Church’s life and mission, but also for human society and culture. Moral theologians have the task, in close and vital connection with biblical and dogmatic theology, to highlight through their scientific reflection “that dynamic aspect which will elicit the response that man must give to the divine call which comes in the process of his growth in love, within a community of salvation. In this way, moral theology will acquire an inner spiritual dimension in response to the need to develop fully the imago Dei present in man, and in response to the laws of spiritual development described by Christian ascetical and mystical theology.”
Certainly moral theology and its teaching are meeting with particular difficulty today. Because the Church’s morality necessarily involves a normative dimension, moral theology cannot be reduced to a body of knowledge worked out purely in the context of the so-called behavioural sciences. The latter are concerned with the phenomenon of morality as a historical and social fact; moral theology, however, while needing to make use of the behavioural and natural sciences, does not rely on the results of formal empirical observation or phenomenological understanding alone. Indeed, the relevance of the behavioural sciences for moral theology must always be measured against the primordial question: What is good or evil? What must be done to have eternal life?
The moral theologian must therefore exercise careful discernment in the context of today’s prevalently scientific and technical culture, exposed as it is to the dangers of relativism, pragmatism and positivism. From the theological viewpoint, moral principles are not dependent upon the historical moment in which they are discovered. Moreover, the fact that some believers act without following the teachings of the Magisterium, or erroneously consider as morally correct a kind of behaviour declared by their Pastors as contrary to the law of God, cannot be a valid argument for rejecting the truth of the moral norms taught by the Church. The affirmation of moral principles is not within the competence of formal empirical methods. While not denying the validity of such methods, but at the same time not restricting its viewpoint to them, moral theology, faithful to the supernatural sense of the faith, takes into account first and foremost the spiritual dimension of the human heart and its vocation to divine love.