The sages in the Talmud (one opinion) tell us that there never really was a perverse and rebellious son. If this is so, the Talmud asks, why were we given a mitzvah which is impossible to fulfill. The answer: This mitzvah was given “to learn about and receive reward”. All this arouses the curiosity. After all, the Torah was given in order that we may fulfill it. If so, what is this strange mitzvah which was given to us, even though we will never be able to carry it out. Would the Torah bring something down which is solely theoretical and for the purpose of making nice “vorts”, but inapplicable in the real world? Would this not contradict the very purpose for what the Torah was given for?
The matter becomes much clearer when we realize that the Torah was given for a much deeper reason than for the sterile and rote carrying out of mitzvot. The Torah was not given so that we arise each morning and with our eyes half-closed put two black leather boxes called “Tefilin” on our arm and head, and then mumble half-heartedly incomprehensible words called “prayer”. The Torah was given with an idea. Behind every personal mitzvah stands an idea, and behind all of the mitzvot together, there stands a general idea. And a person who fulfills the mitzvah with the proper understanding is fulfilling a living mitzvah, with purpose and soul, and is not simply performing some sterile ritual like a monkey.
This is the purpose of the mitzvah of killing the perverse and rebellious son. In truth, it is virtually impossible that all the conditions will exist for us to actualize this mitzvah. In any case, G-d gave us this mitzvah to teach us that even though it might never happen, it is critical for us to understand the idea that stands behind the mitzvah – and it is an idea which is indeed a very practical one!
The idea here is the burning out of evil from the world, and to teach us that doing so is not only good for the world, but it is also for the personal good of the son himself. For the sages say that the perverse and rebellious son is punished for what he will eventually become, and not for what he is now. The Torah, knowing that the day will come when this impetuous lad will steal, rob, and pillage, has taught us in a very effective and powerful way an awesome lesson. Though this perverse and rebellious son has barely turned 13 years old and hardly knows his right from his left, we must kill him nonetheless before his evil starts manifesting itself. And so, despite the fact that the actual carrying out of this mitzvah is limited to almost impossible circumstances, we learn the idea that in our eternal and uncompromising struggle versus evil, there is such a concept of rooting it out before it actually reveals itself.
All this clearly contradicts western culture where even the most blatant evil is not given a death blow, and all for reasons of “ethics”. Judaism is truly merciful, to such an extent that it distances any potential evil that even threatens to do harm, in order to teach us the basic concept of hating evil, and the obligation of the Jew to burn it out.