Yesterday, we noted the fact that the mitzva of pidyon ha-bein, which requires a father to “redeem” his firstborn son by giving money to a kohen, applies only in the case of a firstborn boy, and not when a firstborn is female. This halakha becomes difficult to understand in light of the Midrash’s comment (Shemot Rabba 18:3) that the plague of the firstborn that struck Egypt on the night of the Exodus killed all firstborns, male and female alike. The Torah in the end of Parashat Bo makes it clear that the obligation of pidyon ha-bein serves to commemorate the survival of the Israelite firstborns on the night when their Egyptian counterparts were killed, and the question thus arises as to why the Torah applies this obligation only to male firstborns.
The Chida (Rav Chaim Yosef David Azulai) offers several different answers to this question in different contexts in his writings (documented by Rav Chaim Leib Eisenstein, in his Peninim Mi-bei Midresha). In his Simchat Ha-regel commentary to the Haggadah, the Chida advances the theory that the plague of the firstborn affected the various nationalities in Egypt differently. The Midrash (cited by Rashi to 12:29) comments that God that night killed even the firstborns of people of other nationalities who resided in Egypt (presumably, because they supported or participated in the enslavement of Benei Yisrael). However, the Chida suggests that when the aforementioned passage in the Midrash tells that the plague struck even the firstborn girls, it refers only to the firstborn girls of Egyptian women. As for the other ethnic groups residing in Egypt at the time, the plague struck only the firstborn males. The Chida explains this distinction on the basis of Kabbalistic concepts, but regardless, it emerges that only the male firstborns among Benei Yisrael were in danger that night, since for all foreigners in Egypt the plague struck only the firstborn boys. For this reason, the mitzva of pidyon ha-bein applies only to firstborn males.
Elsewhere, in his Ge’ulat Olam (p. 12a), the Chida cites a different answer from the Ma’aseh Rokei’ach, who notes the Midrashic tradition that Benei Yisrael earned redemption in the merit of the nation’s righteous women. Whereas the males of Benei Yisrael were steeped in sin in Egypt and were thus unworthy of redemption, the women remained righteous and the Exodus occurred in their merit. The Ma’aseh Rokei’ach asserts that since the women were righteous, the female firstborns rightfully deserved to be spared the plague of the firstborns, and it was only the men who depended on God’s special grace and kindness to escape the plague. Therefore, the mitzva of pidyon ha-bein, which acknowledges the special stature of the firstborns, who were spared during the plague, applies only to male firstborns.
The Chida there in Ge’ulat Olam then adds another possibility, noting that the requirement of pidyon ha-bein is associated with the priestly status to which the firstborns were elevated at the time of the Exodus. As we read in Sefer Bamidbar (3:11-13), the firstborns were designated at the time of the Exodus to serve as the “kohanim,” and perform the sacrificial service, but they were later replaced by the Leviyim, the only tribe that did not participate in the sin of the golden calf. The requirement to “redeem” the firstborn, which relates to the special status conferred upon them on the night of the Exodus, is integrally linked to the ritual role they were to have served by virtue of that special status. Therefore, as women do not perform the avoda, the obligation of pidyon ha-bein naturally applies only to firstborn males.