*2352 By masturbation is to be understood the deliberate stimulation of the genital organs in order to derive sexual pleasure. "Both the Magisterium of the Church, in the course of a constant tradition, and the moral sense of the faithful have been in no doubt and have firmly maintained that masturbation is an intrinsically and gravely disordered action."138 “The deliberate use of the sexual faculty, for whatever reason, outside of marriage is essentially contrary to its purpose.” For here sexual pleasure is sought outside of "the sexual relationship which is demanded by the moral order and in which the total meaning of mutual self-giving and human procreation in the context of true love is achieved."139
To form an equitable judgment about the subjects’ moral responsibility and to guide pastoral action, one must take into account the affective immaturity, force of acquired habit, conditions of anxiety or other psychological or social factors that lessen, if not even reduce to a minimum, moral culpability. *
In this case, the Church is saying that there are factors (such as affective immaturity, force of acquired habit, and conditions of anxiety) that would lessen or even reduce culpability to a minimum. If culpability is “reduced to a minimum” that would mean that one did clearly not commit a mortal sin even though any teenager would obviously be “afraid of getting caught” in the act of masturbation.
Yes, but even in this case, there was a first time for doing it, in which the teenager was not yet subject to the forces of acquired habit, or etc., and had the opportunity to know or sense that he was doing something bad. Right?
But if he had no idea that there was anything the matter with it, he wouldn’t be afraid of getting caught - if he believed that it is normal and natural, then he would not experience any fear. And only in this case could we say that after a number of years, he would have acquired a bad habit, after which he finds out that it’s a sin, but at that point, he would have lessened culpability because when he first started doing it (before it became a habit) he didn’t know it was wrong, and it was only after it became a habit that he found out that it was wrong.