Commentaire sur Le Lévitique 23:10

ראשית קצירכם THE FIRST FRUITS OF YOUR HARVEST — This means that it (the Omer) shall be the first thing to be harvested (cf. Sifra, Emor, Section 10 3).

SPEAK UNTO THE CHILDREN OF ISRAEL, AND SAY UNTO THEM: WHEN YE ARE COME INTO THE LAND. Since He establishes a new commandment here in connection with each of the festivals, in addition to their being days of rest and holy convocation, therefore He singled out for each festival a special section, which begins with the charge, Speak unto the children of Israel.²⁴²So also further on in Verse 24 [in connection with the New Year], and Verse 34 [in connection with the Festival of Tabernacles]. The reason why that expression is not found in connection with the Festival of Weeks and the Day of Atonement will be explained in the text. And since the time of the Festival of Weeks is dependent upon the omer,²⁴³Literally: “a measure.” This refers to the meal-offering of the new barley brought on the second day of Passover, which is the sixteenth day of Nisan. From that day on we count the forty-nine “days of the omer,” and on the fiftieth day is the Festival of Weeks. Thus it is clear that the time of this festival is dependent upon the omer. therefore He stated it all in one section. And because the Day of Remembrance [i.e., the New Year] and the Day of Atonement are in one month [Tishri], and both relate to one subject — the [Divine] Judgment concerning man’s sins and the atonement [achieved] by those who do repentance — therefore He did not say concerning the Day of Atonement “speak unto the children of Israel,” since the first statement [about the New Year] was sufficient in this case. He made, however, two separate sections [of the omer and the Festival of Weeks, as also the New Year and the Day of Atonement], because they are different matters.

דבר אל בני ישראל, “speak to the Children of Israel, etc.” Nachmanides writes that the reason why the Torah devotes a separate instruction by G’d for each of these festivals instead of a single introductory heading for all of them, is that each festival contains some legislation which did not apply to the previous one, excepting the Sabbath. The common denominator of all of them is that all are called מקראי קודש, “holy convocations. Since there is no specific date given for the festival of Shavuaot, seeing that the Torah links it to the first day the omer was offered on the 16th day of Nissan and stipulates that the 50th day thereafter must be the festival of Shavuot, it is lumped together in the same paragraph as that legislating the omer offering, an offering which permits the new barley harvest for general consumption from that date on. Also, the fact that both Rosh Hahanah and Yom Hakippurim occur in the same month and represent the beginning and the end of the ten days of penitence, i.e. they cover basically the same subject, at least the words דבר אל בני ישראל, “speak to the Children of Israel,” are not repeated.