Everything we said was to explain the opinion of Tosfos. But the Kesef Mishna doesn't subscribe to this opinion [nor did he subscribe to Sports Illustrated, but that is besides the point]. The KS"M was of the opinion that the act of passing the child through the fire to Molech is not a מעשה that relates to this or that son but rather an act that relates to the generations. When the father passes one son through and then another there IS a צירוף between them because instead of the father performing an act that relates to PART of the generations [as he did with the first son], he is instead performing an act that relates to ALL the generations [if he has two sons]. That is why the KS"M holds that if he passes one son through and then another later on, the status of the first passing changes and is transformed into an act that relates to ALL the generations and he is thus פטור [because of the drasha of מזרעו ולא כל זרעו].
But Tosfos didn't buy it [if it is permitted to say that]. They saw the passing of each child as a different, disparate act, disconnected from the act of passing the other sons. For this reason we have to wonder about the discussion of the Aruch La-ner in our sugya, the Pri Chodosh in his chiddushim on the Rambam, the Minchas Chinuch [208] and many many others who asked about the opinion of the KS"M that when he gives all of his sons to Molech, he becomes retroactively פטור for passing the earlier ones through. If that is true, then he is פטור even if he doesn't pass all of them through because each of the earlier התראה's is a התראת ספק - maybe he will pass them all through and be פטור!! We can't punish if it is only a התראת ספק!!
The Aruch La-ner said that for that very reason Tosfos didn't accept the understanding of the KS"M that one can become retroactively פטור. But of course if that is the case then העיקר חסר מן הספר, because Tosfos didn't breathe a WORD about that. However the Minchas Chinuch [208] and the Binyan Shlomo on the Rambam wrote that there is no issue of התראת ספק according to what Tosfos wrote in a number of places that a Nazir receives Malkus if he transgresses his Nezirus oath and we don't say that it is only a התראת ספק lest he uproot [שואל] the Nezirus since we hold that he has a חזקת נזיר and will stay that way, CERTAINLY here we should hold strongly with the חזקה and assume that he won't pass all of his sons through the fire [see there]. So the התראה for the איסור is considered ודאי! The Mishnas Chachomim in Hilchos Avoda Zara wrote that התראת ספק is only when the ספק is whether he performed an act that would obligate him [מעשה המחייב] and here is different because the act is DEFINITELY a מעשה המחייב and the only question is whether it will be uprooted and "fixed" later [by giving over the rest of his sons]. Such a case is not a התראת ספק.
But based on what we said there was no מעשה המחייב according to the KS"M in the first place if it turns out that the first one was passed over the fire as part of the passing over of ALL the generations for which there is no חיוב. So this is not a מעשה המתקן - a fixing, but rather it emerges retroactively that there was never a מעשה המחייב in the first place. So then we must say [in order to avoid the התראת ספק problem] like Tosfos that it IS a תיקון because each son is viewed individually.
On the other hand, according to our explanation of Tosfos that it is a תיקון, then we can employ the סברא of the Mishnas Chachomim that it is not a התראת ספק because his first act was DEFINITELY a מעשה המחייב and the only question is whether it will be fixed later [by passing his other sons through as well]. Therefore we can't say like the Aruch La-ner that Tosfos didn't accept the opinion of the KS"M because they hold that it is a התראת ספק, because according to the Mishnas Chachomim - it ISN'T! In fact, Tosfos holds that it is PASHUT that he will not be פטור for the first one retroactively and thus they explained that the only cases where he will be פטור for כל זרעו is where he passed them through simultaneously or he had only one son.
WOW! 😀😀
