Roman Catholic teaching on morality is based on human acts, also called concrete acts. A human act is the knowing choice of a human person. Such acts are termed “concrete” because the act and its morality are real and meaningful, not merely an abstraction. The morality of each and every act is determined solely and entirely by three fonts (or sources). An act with three good fonts is always morally permissible. It might not be particularly virtuous, but it is not a sinful act. An act with one or more bad fonts is always a sin. It is objectively contrary to the eternal moral law, and is never morally permissible.
1. The first font is called intention. It is the intended end chosen by the person who acts. This font resides in the person. The intention is the purpose or reason for choosing the act itself.
2. The second font is called moral object. The moral object is the end, in terms of morality, toward which the knowingly chosen act is inherently ordered. However, the whole font is not solely the object, but rather the knowing deliberate choice of a concrete act (the act in a particular case) along with its moral nature and moral object.
Every concrete act has three parts: (a) the act itself, (b) the moral nature of the act, which is its inherent moral meaning before the eyes of God, (c) the moral object. The moral nature of the act itself is nothing other than the ordering of the act toward its moral object. An act ordered toward an evil object is intrinsically evil and therefore always immoral.
These three parts are inseparable. When a human person knowingly chooses any act, that choice necessarily always includes, at least implicitly, the moral nature and moral object of the act. And the moral nature is inseparable from the act itself because the nature of a thing cannot be separated from the thing itself. The nature of any act is inherent to the act itself.
Thus, the chosen act is not merely a shell, into which one might place whatever good or evil purpose one wishes. Knowingly chosen acts have an essential moral nature or inherent moral meaning, which resides in the act, not in the person who acts. And that is why the choice of any intrinsically evil act never becomes moral, even when done for a good purpose, in a dire circumstance.
Why should an exterior act be considered always immoral to choose? How is it that a mere physical action could have moral meaning? The answer is quite simple. The acts of human persons, whether interior acts (confined to the mind and heart), or exterior acts, are the knowing and deliberate choices of persons who are made in the image of God, persons who understand transcendent truths, such as good and evil, persons who are responsible before God and neighbor for the good or evil that they do.
Some ethicists have attempted to justify certain popular intrinsically evil acts by separating the physical action from its moral meaning. But this approach is condemned by the Magisterium: “A doctrine which dissociates the moral act from the bodily dimensions of its exercise is contrary to the teaching of Scripture and Tradition.” [Veritatis Splendor 49].
3. The third font is the circumstances of the act, which is the reasonably anticipated good and bad effects (or consequences) of that knowing choice. If the reasonably anticipated good consequences equal or outweigh the reasonably anticipated bad consequences, then the third font is good. A good act done with good intentions is moral, if the good and bad effects are equal, or if the good morally outweighs the bad.
Many false teachers in the Church today are preaching and promoting various clever distortion of magisterial teaching, in order to justify certain popular intrinsically evil acts, such as contraception and grave sexual sins. But the teaching of the Magisterium is clear and definitive: “No circumstance, no purpose, no law whatsoever can ever make licit an act which is intrinsically illicit, since it is contrary to the Law of God which is written in every human heart, knowable by reason itself, and proclaimed by the Church.” [Evangelium Vitae 62].
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