What exactly is the significance of the fulfillment of the mitzva of counting by the court?
Rav Soloveitchik suggested that indeed there are two fulfillments, and it is possible that a blessing is recited over only one of them, and it is possible that this is connected to the matter of days and weeks. But both fulfillments are connected to a principle put forward by Rav Chaim regarding shemitta and yovel.
The Gemara in Arakhin speaks of the situation in which the court counted shemitta years in order to know when the yovel year falls out. Rav Chaim explains that if we examine the verses at the beginning of Parashat Behar, the question arises: What turns the yovel into the fiftieth year? It would seem from the verses that the answer to this question is the fact that this year was preceded by a count of forty-nine years. According to this, we can explain the position of the Chizkuni, that the count of the court is not a separate mitzvain its own right, but rather it is a preparation for a mitzva, in order to know when to observe the mitzva of yovel, and therefore a blessing is not recited over it.
Rav Soloveitchik suggested something similar with respect to the festival of Shavuot. There is something strange about Shavuot. We know that there is a fundamental difference between the sanctity of Shabbat, which is fixed, and the sanctity of the festivals, which stems from the sanctification of the month by the people of Israel. Shavuot, so it would seem, takes place independently of the sanctification of the month by the people of Israel, as it falls out fifty days after Pesach, independent of the sanctification of the month of Sivan.
Of course, it could be argued that the sanctification of the month of Nisan is what sanctifies the festival of Shavuot, but Rav Soloveitchik proposed a different understanding.
In order to understand this approach, one must analyze the view of Rav Chaim. What is the fulfillment of sefirat ha-omer? There is the act of counting itself and there is also the connection to the omer offering. The festival of Shavuot is sanctified by the count, i.e., by the count made by the court. In addition, there is a mitzva of counting, which must be fulfilled by each and every individual. It turns out, then, that there are two separate fulfillments of the mitzva of sefirat ha-omer, and it is possible that in this way we can distinguish between the obligation to count the days, which is connected to the act of the mitzva itself, and the obligation to count the weeks, which is connected to the sanctification of the festival of Shavuot done by the court. (Thus, we can accept Rabbeinu Yerucham’s principle but not his conclusion.)
Rav Soloveitchik went further than this and asserted that Shavuot is sanctified not only by the court’s counting, but even by the individual’s counting. This follows from several points, two of which I shall mention here.
There is much discussion regarding the relationship between counting at night and counting during the day. Tosafot in Megilla (20b, s.v. kol ha-laila) cite the position of the Halakhot Gedolot:
The Halakhot Gedolot writes that if a person forgot to count at night, he should count the next day without a blessing. And this is the halakha.
Why must one count without a blessing? The accepted ruling nowadays is that one who forgot to count at night counts during the day without a blessing, but this is because we are in doubt whether one may count during the day or not. But the Halakhot Gedolot had no such doubt. Why, then, was he of the opinion that one should count without reciting the blessing?