Can a boy who becomes Bar Mitzva in the middle of Sefiras HaOmer continue counting the Omer with a Beracha?
Tosafos in Menachos 66a quotes the Bahag that if someone missed counting a day of Sefiras HaOmer altogether, he can no longer continue counting with a Beracha because the counting must be “Temimos”, complete.
Tosafos personally expresses skepticism at this ruling. The Rosh in Pesachim 10:41 elaborates that Tosafos considers each individual day’s count to be a separate and independent Mitzva; consequently, omitting one has no impact on the others.
It is not completely clear whether the Bahag opines that counting all 49 days merely completes one single Mitzva, or perhaps he agrees that each day is a separate Mitzva, but “Temimos” makes them interdependent.
The Shulchan Aruch OC 489:8 rules that we must be Machmir for the Bahag’s position, and one who forgot to count one day should not continue with a Beracha. However, he does not conclusively rule in accordance with the Bahag; it is merely a doubtful situation where a Beracha is not recited.
Consequently, in the Beis Yosef he concurs with the Terumas HaDeshen 1:37 that if one is uncertain whether he remembered to count a certain day and is unsure if he omitted it, he may continue to count the following days with a Beracha. Since there is doubt what occurred, and even if he forgot the ultimate Halacha is questionable; the rule of Sfek Sfeika allows him to continue saying Sefiras HaOmer with a Beracha.
The Sefer HaChinuch Mitzva 306 explains the Bahag’s position as considering the counting of all 49 days as one single Mitzva.
In this context, the Minchas Chinuch there addresses our original question regarding the Bar Mitzva Bachur who is lacking in a portion of the Mitzva since he only counted the earlier days as a non-obligated minor. He concludes that the Bachur may continue to recite the Beracha for a fascinating reason.
The Magid Mishna Shabbos 29:11 writes that if one made early Shabbos and said Kiddush before sunset, he may continue eating after nightfall based upon that Kiddush. The Mordechai Megila §798 adds that even according to the opinions that Tosefes Shabbos is exclusively of Rabbinic origin while Kiddush on Shabbos is a Biblical obligation, the Rabbinic Kiddush he recited before sunset can be utilized to fulfill his Biblical requirement. The Magen Avraham in Orach Chaim 267§1 quotes the Magid Mishna and Mordechai.
Based upon this precept, the Minchas Chinuch suggests that in our case as well, we can apply a similar concept. Since a minor is required to perform all of the Mitzvos, including Sefiras HaOmer, due to the Rabbinical obligation of Chinuch; his counting prior to the Bar Mitzva can count towards his subsequent Biblical obligation. Consequently, though the status of his counting has changed mid-stream, his situation is vastly different than that of one who failed to count at all.
The need to originate such a comparison is clearly predicated on his acceptance of the Sefer HaChinuch’s understanding of the Bahag. Only assuming that all 49 days are single Mitzva makes it necessary to explain why a Rabbinic fulfillment can combine with a Biblical one to create a “complete” Mitzva. However, if we interpret the Bahag’s requirement of “Temimos” as merely conditioning his count on physically counting each and every day, it is irrelevant whether he fulfilled any obligation at all. In fact, there are Rishonim who opine that one must count every day, but if one was omitted it is sufficient to recite the next day, “Yesterday was x and today is y”. This clearly does not fulfill the missing Mitzva, it merely rounds out a complete count.
The Maharam Shick on Mitzva 307 challenges the Minchas Chinuch’s conclusion for a different reason. While it is true that the Magen Avraham cited the Mordechai’s words, in fact his conclusion was to disagree. The Magen Avraham disputed the Modechai’s ruling based upon the Halacha that a minor cannot exempt an adult by reciting Birkas HaMazon for him. Clearly, it is not conclusive that a Rabbinic obligation can exempt a Biblical one.
The Maharam Shick resolves the Magen Avraham’s question by differentiating between the types of Rabbinic precepts. While regarding Kiddush the same individual who has the Rabbinic obligation before nightfall will have the Biblical one later, this is not straightforward regarding Chinuch. In Berachos 48b Rashi writes that the imperative of Chinuch is incumbent upon the father and not the son. According to his opinion, a minor has no Rabbinic obligation to recite Birkas HaMazon or Sefiras HaOmer at all; rather, his father is commanded to educate and train him by doing so. While Tosafos there disagrees, the matter is not resolved.
Consequently, the Maharam Shick concludes that while the Magen Avraham’s challenge to the Mordechai from Birkas HaMazon can be resolved by this distinction, the Minchas Chinuch’s comparison would not be valid as the Mitzva of counting the first half of Sefira was not fulfilled in any manner, even Rabbinic. Ultimately, while he disputes the Minchas Chinuch’s reasoning, in Teshuvos Orach Chaim 2:269 he concurs with the Minchas Chinuch’s ruling permitting the continuation of Sefira with a Bracha for other reasons.
In conclusion, it would appear that the majority of Poskim conclude that a Bar Mitzva Bachur who counted Sefiras HaOmer every day prior to his Bar Mitzva should continue to do so with a Beracha. Even if we would consider this ruling questionable, we mentioned previously that there is precedent to count with a Beracha in the presence of multiple doubts, which certainly exist here. First of all, it is not certain that the Halacha follows the Bahag altogether. Secondly, the intent of the Bahag may be merely to require counting 49 days, which was satisfied; but not necessarily fulfilling the Mitzva 49 times. Even if it does, many of the Poskim suggested various justifications to continue counting with a Beracha regardless.