“The judgment of the Egyptians [lasted for] 12 months” (Eiduyos 2:10). There is much discussion about what this “judgment” consisted of, and how it could have lasted for 12 months. The starting point for much of the discussion is Rashi’s explanation of the “seven days” given for length of the plague of blood (Sh’mos 7:25); “the plague was active for a quarter of a month (the seven days mentioned in the verse) and [for] three [quarters of the month] he (Moshe) warned them (about the plague).” If each plague lasted for one month, and there were 10 plagues, the “judgment of Egypt” should have only lasted 10 months, not 12. Why are there two additional months that are considered part of the “judgment of Egypt,” and what was happening that it qualifies as part of their judgment? Numerous approaches have been suggested to deal with this issue.
Y’feh To’ar, commentating on Sh’mos Rabbah (9:12, the Midrash that Rashi is based on), says explicitly that this Midrash is not consistent with the Mishna in Eiduyos, as according to the Midrash the “judgment of Egypt” must have only lasted nine months (one month each for the first nine plagues; the tenth plague followed immediately after the ninth, so no additional time had passed). However, there is no need (aside from thereby sidestepping having to reconcile the Mishna with the Midrash) to say that the term “judgment” must refer to the actual plagues. As a matter of fact, the Vilna Ga’on, in his commentary on Seder Olam (3) saying that “the plagues of Egypt [lasted] 12 months,” says that Seder Olam does not literally mean “the plagues,” as the 12 months started from the time G-d spoke to Moshe at the burning bush, which Seder Olam (5) says was during the time of Pesach. (The Ga’on brings a couple of proofs that Seder Olam could not have meant that the actual plagues lasted 12 months.) Therefore, even though attributing the discrepancy between the Mishna and the Midrash to a difference of opinion avoids having to attempt a reconciliation, the attempt to understand what the Mishna meant by “the judgment of Egypt” is much more inviting than just sweeping the issue aside.
Midrash Seichel Tov is among the commentators who count incomplete months in the number 12. Moshe and Aharon came to Paro (Pharaoh) at the end of Iyar in 2447, and the nation left in the middle of Nisan 2448, so when you add those two partial months to the ten complete months in between them, you have a “judgment” of “12 months.” Among the issues this approach has to deal with is that the “12 months” of the “judgment of the Egyptians” is just one set of “12 months” listed in the Mishna, and the others seem to be complete months without having to count any partial months. As a matter of fact, if we count partial months as months, the “generation of the flood” would have been judged for 13 months, not 12, as Noach entered the ark on the 17th day of the 7th month (B’raishis 7:11) and the land “dried” on the 27th day of the 7th month of the following year (B’raishis 8:14, with the extra 11 days completing a solar year).
Rav Yaakov Emden (Lechem Shamayim, his commentary on the Mishna) suggests that Moshe went to see Paro in the middle of Nisan (2447) to ask him to send G-d’s people out, at which point G-d started “sitting in judgment of the Egyptians” and Paro started to feel G-d’s punishment (as his power was being challenged). A month later (in the middle of Iyar), Moshe went back to Paro, which was when he and Aharon did the snake/stick trick (Sh’mos 7:10). After another month (in the middle of Tamuz) the process of the first plague began when Paro was warned it was coming if he didn’t back down. By adding two months before the first plague, and explaining why they were considered part of the “judgment of Egypt,” our issue has been resolved. However, other issues are now raised in its place.
For one thing, Seder Olam uses Iyar as a reference point in his timeline (how it is used depends on how his timeline is understood, a matter of discussion that we will put aside for now) because that is when the straw Paro made the Children of Israel start to collect (Sh’mos 5:7) is available in the fields. Paro added this task right after Moshe’s first trip to see him, which Rabbi Emden says was in the middle of Nisan, not in Iyar. Nevertheless, Seder Olam (5) says that Moshe spent a week trying to get out of being the person to take the nation out of Egypt, meaning that he left the “burning bush” with only a week left in Nisan, not halfway through it. And he went back to Midyan to get his family and take leave of his father-in law (Sh’mos 4:18-20) before heading to Egypt, which had to take more than one day (since G-d had to tell Moshe again in Midyan to go back to Egypt, see 4:19, and he stayed at an inn on the way to Egypt, see 4:24). All of this occurred before going to Paro, meaning that Moshe didn’t see Paro the first time until the very end of Nisan (at the earliest), which fits with the “straw season” being in Iyar. Although this removes the possibility of there being exactly 12 months from Paro’s first refusal to send the Children of Israel out until they actually left Egypt, if we include the drowning in the sea as part of their “judgment” (which is quite reasonable), we are off by only a couple of days.
Other issues with this approach that need to be resolved are the Midrashim (e.g. Bamidbar Rabbah 11:2) that say Moshe disappeared for three months after he saw Paro the first time before going back to see him the second time, as well as the fact that a month is not needed for the tenth plague (Rabbi Emden only accounts for two “missing months,” not three). However, if the plagues started a month later (in Av), and we move the “snake/stick” scene to shortly before the first plague, we have a three month interval between Moshe’s first visit to Paro and his second.
Midrash HaGadol (7:25) is among the sources who say that even though each plague lasted for a month, there was a week in between one plague and the warning of the next one. First Moshe would warn Paro about the upcoming plague for (approximately) three weeks, then the plague would last a week (to complete the month), then G-d would wait a week before sending Moshe to warn Paro about the next one. If we take away the week between the ninth and tenth plagues (since they came back-to back), and don’t give the tenth plague its own month (since the nation left the next day), we are still one month short. Nevertheless, if we don’t need a three week warning before the third, sixth and ninth plagues either (since the Torah doesn’t mention Moshe going to Paro before these plagues), we now have three months plus an additional week that we can assign to Moshe’s disappearance. Some (e.g. Or Hachayim on Sh’mos 7:25) say that when Paro asked Moshe to remove a plague, that plague didn’t last the full week. If that plague’s “month” was thereby cut short, and the week between plagues started right away rather than waiting until the previous plague would have ended, the extra week above and beyond the three months attributed to Moshe’s disappearance could easily be accounted for.
Seder HaDoros has Moshe’s three month disappearance coming after the first plague. By adding three months to the nine months of the first nine plagues, the “12 month judgment” started with the first plague and ended after the tenth plague. However, the first plague couldn’t have started until, at the earliest, the very end of Nisan 2447 (accounting for the week spent by the burning bush, the trip to and from Midyan, the first two trips to Paro (made before the third trip when Paro was warned about the first plague, see Sh’mos 7:14-17), and all that happened in between those first two trips (such as adding to the chores of the slaves, the complaints to Paro about it, the complaints to Moshe for making things worse, and Moshe’s complaint to G-d for making it worse, see 5:6-23), while the tenth plague hit in the middle of Nisan 2448, leaving us about a half a month short of 12 months. Additionally, Moshe’s three month disappearance can be easily explained if it occurred after his first trip to Paro made things worse (the Midrashim that mention his disappearance are discussing this time period). But why would Moshe disappear for three months after the plagues had already started?
[It should be noted that some Midrashim (e.g. Sh’mos Rabbah 5:20) have Moshe disappearing for six months, not three. It is obviously much more difficult to make this time frame work if each plague lasted a month and we are limited to a 12 month period of time. (Midrash Seichel Tov says that according to this opinion the plagues started in Sh’vat — hence its name, which connotes a stick of retribution — with each plague lasting a week, i.e. ten plagues in ten weeks.)]
The most straightforward timeline is the one put forth by Y’feh To’ar (see also Y’day Moshe), despite the fact that he says there’s no need to reconcile the Mishna with the Midrash about the length of each plague. (He doesn’t get as specific as I am about to get.) Moshe agreed to go to Paro after a week-long discussion at the burning bush, a discussion that started on what would become the first day of Pesach. The “12 months” of the “judgment of the Egyptians” started after Moshe agreed to go, and ended when G-d “threw the [Egyptian] chariots and horseman into the sea” a week after the nation left Egypt. Moshe disappeared for three months after his first visit to Paro because he was so distraught about things having become worse. Although Y’feh To’ar says that each of the first nine plagues last a month (even those where no warning is mentioned in the Torah), it is more likely (as many commentators say explicitly) that there was no warning before the third, sixth or ninth plagues (as each set of three plagues taught a specific message, and once a warning was ignored the first two times for each message, there was no third warning). This gives us an additional nine weeks (or more, if the warnings were longer than 21 days and/or the week of the actual plague was shortened when Paro temporarily gave in), but it allows for a healthy amount of time for Moshe’s return to Midyan, his first trip back to Egypt, and the time between the “snake/stick” showdown and Moshe being instructed to warn Paro about the first plague. As long as we aren’t limited to the “12 months” starting with the first plague (and the Vilna Gaon presents a strong argument why we are not), and the “judgment of Egypt” can start when everything was set to begin their punishment (i.e. Moshe agreeing to be G-d’s messenger), there is no contradiction between the formula for each plague being three weeks of warning plus one week of implementation and the “judgment of Egypt” lasting 12 months.