Tetzaveh: Chapter 7
Matzot and the counting of the Omer

We read that in order to raise Malchut to be connected with the supernal days above, men must stand on their feet to count the Omer. The counting of the Omer is the secret of the male, being connected to the Holy Covenant, so women are exempted from this counting. Rabbi Shimon says that throughout the seven supernal days of Zeir Anpin, one of the lower days of Malchut becomes holy, and this lower day is called a week. When the seven Sfirot of Malchut are sanctified through the 49 supernal Sfirot, the House is prepared so that Malchut can join with Zeir Anpin; then it is called Shavuot. Then the fiftieth day, Binah, rules over the 49 days and, by way of awakening the lower beings, produces the Torah.