What is the connection between the Korban Omer and Sefiras ha'Omer on Pesach, and the Shtei ha'Lechem on Shavu'os?
Ramban: One begins to count the Omer at the beginning of the barley harvest, on the day that one brings the first produce of the new barley crops together with a Korban; whereas the Shtei ha'Lechem comprises the first produce of wheat, which is also brought together with a Korban.
Until when does one count the Omer?
Rashi: Up to the end of the seven-week period 1 - forty-nine days.
Rashi: Because the word "Ad" (in the phrase "Ad mi'Mochoras ha'Shabbos ha'Shevi'is" is exclusive.
How do the words "Chamishim Yom" fit into the Pasuk?
Rashi #1: "Chamishim Yom" goes together with the following phrase, 1 to read "Chamishim Yom v'Hikravtem Minchah Chadashah La'Shem".
Rashi #2: One needs to invert "Tisperu" and "Chamishim Yom", in which case "Chamishim Yom" goes together with "mi'Mochoras ha'Shabbos ha'Shevi'is, with which it is synonymous.
Hadar Zekenim: It means forty-nine, since in Re'eh (Devarim 16:9) the Torah writes "Shiv'ah Shavu'os". 2
Sifra: It means that, after counting forty-nine days, we must celebrate the fiftieth. 3 "Sheva Shabbasos Temimos" teaches us not to count fifty days and celebrate the fifty-first, and "Tisperu Chamishim Yom", not to count forty-eight and celebrate the forty-ninth.
Rosh: Proof of this lies in the Neginah (the note) Tipcha on the word "Tisperu," which indicates that it refers to what came before, and not to "Chamishim Yom." (Also, there is an Esnachta under "Yom" indicating that "Chamishim Yom" is not read together with "v'Hikravtem" - PF).
This is similar to "Arba'im Yakenu" in Ki Seitzei (Devarim 25:3), which means thirty-nine.
See Torah Temimah, note 56.
Why are the Shtei ha'Lechem called "Minchah Chadashah"?
Rashi and Rashbam: Because it is the first Korban that is brought in the Beis-Hamikdash 1 from the new crops. 2
Ramban: Because it is forbidden to bring a Minchah from the new crops before having brought the Shtei ha'Lechem.
Seforno (on Pasuk 17): To teach us that the Shtei ha'Lechem are brought from the first crop of wheat. 3
Rashbam: Because it is the time when the new wheat-crop ripens.
Rashi: Even though the Omer preceded it, the Omer is different inasmuch as it consistes of barley, whereas all other Menachos (with the sole exception of the Minchas Kena'os of a Sotah) consist of wheat.
Seforno: Which explains why (in the following Pasuk) it is called 'Bikurim' (See also in Pinchas, Bamidbar 28:26). And this in turn, explains why Shavu'os is called 'Chag ha'Bikurim.'
Why does a Zav or Zavah not count their days of Taharah with a Berachah? He (or she) is similarly commanded, "v'Safar Lo" or "v'Saferah Lah" (16:13, 16:28)!
Rosh, Moshav Zekenim: A Zav or Zavah cannot count with a Berachah, lest he or she see (Zivah or blood, which cancels the count).
How will we reconcile the words "Tisperu Chamishim Yom" with the Pasuk in Re'eh (Devarim 16:9), "Shiv'ah Shavu'os Tispar Lach"?
Moshav Zekenim: This teaches that it is a Mitzvah to count both the days and the weeks. 1
Since we hold like R. Yossi that the Torah was given on the seventh of Sivan,why do we say on the sixth (the first day of Shavu'os) 'Zeman Matan Toraseinu'?
Hadar Zekenim: Since there is only one day until Matan Torah, this is not a problem.
Ha'Kesav ve'ha'Kabalah: The Torah did not make Shavu'os dependent on Matan Torah but, on Sefiras ha'Omer. Chok Ya'akov (494:1) - this is like the Rivash (96), that we are not concerned if Shavu'os falls on the fifth of Sivan (when they were Mekadesh the month via witnesses), even though all agree that Matan Torah was on the sixth or seventh. 1
Magen Avraham (Reish 494, citing Asarah Ma'amaros): This is a hint to Yom Tov Sheini of Galus 2 (the second day of Shavu'os). 3
How is this like Rivash who taught that we are not concerned for the day of the month, only for the fiftieth day from the Omer. Here, we ask why we say 'Zman Matan Toraseinu' on the wrong day of the Omer! (PF)
Chok Ya'akov (494:1): Why is the day of Matan Torah Yom Tov Sheini? Moreover, the answer does not apply to the B'nei Eretz Yisrael, who observe only one day?
Also refer to Bereishis 1:31:2.2; and to Shemos 19:15:1.5:1 with note 3.
Why do we not recite a Berachah over counting the years until Yovel, where the Torah also writes "v'Safarta Lecha" (25:8)!
Moshav Zekenim: Because only Beis Din is commanded to count the years until Yovel. And maybe they did recite a Berachah.
