Yesterday, we noted Moshe’s warning to Pharaoh before the onset of the plague of blood, “I will hereby strike the water that is in the river with my staff, and it will transform into blood” (7:17). Moshe’s wording seems difficult in light of the fact that, as we read several verses later (8:1), it was Aharon, and not Moshe, who struck the river with his staff to change the water into blood. While we might at first explain that Moshe attributed this action to himself as Aharon performed the act at his behest, this explanation would need to be reconciled with the view of Tosafot (Bava Batra 82a) regarding the case of one who sends his bikkurim to the Temple through a messenger. Tosafot maintain that the person in this case does not recite the mikra bikkurim declaration that is normally recited when one brings his first fruits to the Mikdash, because he cannot recite the phrase, “I have now brought the first fruits of the land.” This seems to imply that a person cannot speak of himself as having performed an act which he commissioned somebody else to perform on his behalf. How, then, could Moshe announce to Pharaoh that he – Moshe – would be striking the waters of Egypt to bring about the plague of blood?
Rav Chaim Leib Eisenstein, in his Peninim Mi-bei Midresha (Parashat Vaera), suggests distinguishing in this regard between bikkurim and other contexts. He cites Rav Meir Dan Platzky’s discussion in his Keli Chemda (Kuntrus Ha-milu’im, Yitro 4) about Tosafot’s position, in which he proposes a novel explanation for why one cannot speak of himself bringing bikkurim if this was done by somebody else on his behalf. Rav Platzky notes that the Torah specifically commands one to hand his first fruits to the kohen in the Beit Ha-mikdash: “The kohen shall take the basket [of bikkurim] from your hands” (Devarim 26:4). Possibly, Rav Platzky writes, the Torah established bikkurim as a mitzva that must be performed with one’s body, similar to placing tefillin on one’s head and arm, in contrast to mitzvot which require achieving a specific result, like charity or other obligatory donations to kohanim. As such, one who sends bikkurim to the kohen performs only one aspect of the mitzva – transferring the bikkurim to the kohen, but does not fulfill the requirement to physically hand the bikkurim to the kohen. For this reason, he is incapable of speaking of himself as having brought the fruits to the Beit Ha-mikdash, as his mitzva is deficient. If so, Rav Eisenstein notes, then Tosafot’s ruling is limited to the narrow context of bikkurim, and does not affect other areas. Hence, we can easily understand why Moshe can speak of himself as bringing the plague of blood, which was done by his brother at his behest.
Rav Eisenstein further notes that the Tur, in his commentary, presents two simple solutions to the question of why Moshe described himself as bringing the plague of blood. First, he writes, some suggest that this verse was written in a kind of shorthand, as we find in many places in the Biblical text, and in truth Moshe said to Pharaoh that he would be appointing somebody to strike the waters of Egypt. The Tur himself explains differently, noting that Aharon was Moshe’s “spokesperson” who communicated Moshe’s warnings and predictions to Pharaoh. It was therefore accurate for Moshe to say, “I will hereby strike the water that is in the river with my staff,” as these words were actually spoken to Pharaoh by Aharon, the one who indeed struck the water.