The Rashi of the Week Parshas Bo

The Rashi of the Week | January 22, 2026

Rashi in His Own Words

Shemos 11:4: Moshe said, "So said the Lord, At the dividing point of the night, I will go out into the midst of Egypt."

Rashi Heading - At the dividing point of the night: When the night is divided. כַחֲצֹּת is like (II Kings 3:20) “when the meal offering was offered up (כַעֲלוֹת)”; (it is also like) (Tehillim 124:3) “when their anger was kindled (בַחֲרוֹת ) against us.” This is its simple meaning, which fits its context that חֲצֹּת is not a noun denoting a half. Our Rabbis, however, interpreted it like כַחֲצִי הַלַיְלָה, at about midnight (lit., half the night), and they said that Moshe said כַחִצֹּת, about midnight, meaning near midnight, either before it or after it, but he did not say בַחֲצֹּת, meaning at midnight, lest Pharaoh’s astrologers err and say, “Moshe is a liar.” But the Holy One, blessed be He, Who knows His times and His seconds, said בַחֲצוֹת, at midnight.

Synopsis

This week's Torah portion, Bo, tells us of the last of the ten plagues. Moshe warned Pharaoh of the tenth plague, the smiting of the firstborn, with the words, "Moshe said, 'So said the Lord, At the dividing point of the night, I will go out into the midst of Egypt.'"

The words "at the dividing point of the night" seem somewhat ambiguous. The words can be translated as written. However, they can also be translated as "at about midnight." Rashi uses both translations. As usual, we ask why Rashi needs two translations. This is especially true in this instance, because Moshe said at approximately midnight. As the Talmud asks, is it possible that Hashem wasn't sure of the time? Instead, as Rashi explains, Hashem told Moshe that He would come at exactly midnight. Moshe, fearing that the Egyptian astronomers would miscalculate, changed G-d's words from "at midnight" to "at about midnight."

Among the other questions is why Hashem needed to give a specific time for the plague to occur. This was not the case with most of the plagues. Additionally, telling Pharaoh that it would happen at or about midnight was of no benefit to him. Moshe did not tell him what day it would take place.

Rashi actually answers all these questions with his definition. Moshe was telling Pharaoh that G-d Almighty would carry out this plague. He and he alone can distinguish between one moment and the next.

Rashi's Explanation

In this week's Torah portion, Bo, we are told that "So said Hashem, 'כחצות הלילה – Kachatzos Halayloh - when the night is divided / at about midnight,' I will go out in the middle of Mitzraim." This was the prelude to the tenth and most severe plague, when G-d Almighty smote the firstborn of Egypt.

As you can see, Rashi translated the Hebrew phrase "Kachatzos Halayloh" with both possible translations. The first is as follows. The Hebrew prefix "כ - Ka," has various translations. It can mean "when." The word "חצות -Chatzos," can mean "it is divided in half." The word "הלילה - HaLayloh," means "the night." Hence, "כחצות הלילה - Kachatzos HaLayloh" means "when the night is divided in half." The Hebrew prefix "כ - Ka," can also be translated as "approximately." The word "חצות - Chatzos," can also mean the noun "midnight," i.e., half of the night. Based on this translation, "כחצות הלילה - Kachatzos HaLayloh" would mean "at approximately midnight."

Rashi gives us both translations. Rashi first quotes the words from the verse "Kachatzos HaLayloh - כחצות הלילה" and tells us that they mean "when the night is divided." He then continues, presenting various proofs that, in this grammatical form, a noun can be used as a verb. He writes that " 'when the meal offering was offered up - .כעלות' (He then cites another example from a verse in Tehillim) 'When their anger was kindled - בחרות against us.' (He continues stating that) this is its simple meaning, which fits its context, that חצות is not a noun connoting a half."

Rashi then offers the second translation. "Our Rabbis, however, interpreted it as כחצי הלילה - about midnight. They said that Moshe said about midnight, meaning either slightly before or after midnight. Moshe did not say at (precisely) midnight. (He was concerned that) The Pharaoh's astrologers would miscalculate and say that Moshe is a liar. (According to many versions of Rashi, including ours, he finishes his explanation with the words). "But Hashem, Who knows His times and His seconds (actually) said ' at midnight,' "In other words, although Moshe generally repeated what Hashem said verbatim, in this instance, he changed Hashem's words. The idea was that even for the fraction of a second by which the Egyptians may have miscalculated, they would not think that Moshe, and consequently Hashem, was not telling the truth.

The supercommentary to Rashi, Sefer HaMizrachi, as well as others, explains that Rashi offers both translations to address an apparent difficulty in the verse. It is the same question the Talmud asks: "Does G-d have a doubt?" If the verse is using the words "חצות הלילה - Chatzos HaLayloh" as a noun, meaning midnight, Moshe is declaring that G-d said that He will slay the firstborn at about midnight. Yet it's impossible to say that Hashem does not know the exact time! Why would G-d approximate the time?

To explain this, Rashi cites two explanations. The first is that "חצות הלילה - Chatzos HaLayloh" is not used as a noun meaning "midnight." It instead expresses the night as divided. The prefix "כ - Ka" means "when." According to this explanation, Moshe is announcing that Hashem said that "at the exact moment when the night is divided in two, i.e., midnight, He will go out to Egypt and smite the firstborn.

According to Rashi's second explanation, the question is also explained. G-d did not say that he would come out at about midnight. He told Moshe that he would come "at midnight." However, to avoid the Egyptians suspecting that G-d is not aware of the exact time, Moshe changed Hashem's words from "at" to "at about."

Difficulties in Understanding Rashi

We assume that when someone says "about" or "approximately," they are expressing doubt. Why should we believe that? Perhaps Hashem was going to go out in Egypt a few minutes before or after midnight. This is especially true in light of the question that the Levush asks; people very often say "approximately" because they are rounding off a number rather than using a precise amount.

The seemingly obvious answer is that it says further on that "it happened at midnight that G-d smote every firstborn in Egypt." This makes it clear that the killing of the firstborn was at precisely midnight, neither later nor earlier. However, we cannot say that Rashi is basing his commentary here on something that the Torah will say later. One of the principles Rashi consistently follows is that he does not rely on a beginner knowing a verse he has not yet learned.

Rashi states regarding his first explanation that "this is its simple meaning which fits its context, that 'חצות - Chatzos' is not a noun denoting a half." However, in his second explanation, he says that, "Our Rabbis, however, interpreted it as 'כחצי הלילה - at about midnight.'" Rashi says this is a Midrashic, Aggadic explanation. Why does Rashi consider the first explanation, Peshat – the simple meaning of the verse? Why should explaining the Hebrew word "חצות - Chatzos" as meaning "when the night is divided" be more in keeping with Peshat than describing it as a noun, "midnight"? This word is used in two other places in the Tanach, and in both places, it means midnight! We must say that when Rashi concludes his first explanation and writes that "this is its simple meaning ... that 'חצות – Chatzos' is not a noun denoting a half," he means that to have the word fit into its present context, we must translate it differently than usual.

Why is Moshe so concerned that perhaps Pharaoh's astrologers will suspect that he is a liar? Ultimately, all of the firstborn of Egypt will die simultaneously within moments of the time that Pharaoh's "scientists" calculated is the midpoint of the night. They will know that he was telling the truth. Why would this be a reason to change G-d's words?

According to our version of Rashi, he concludes his commentary with the words "but Hashem Who knows His times and His seconds (actually) said ' at midnight' (rather than ' at about midnight' as said by Moshe)." We have stated many times that even when Rashi quotes Midrashic material from the Sages, he quotes only those parts that explain Peshat. Why does Rashi say that G-d told Moshe "at midnight," which forces us to say that Moshe changed Hashem's words? Perhaps Hashem, realizing that the Egyptians would not know the exact moment of midnight, actually told Moshe to say "at about midnight."

Rashi is precise about the words that he quotes for the heading of his commentary. Why does Rashi cite the words "כחצות הלילה – when the night is divided / at about midnight," when he is not explaining the word "הלילה – night?" All that he is explaining is the word(s) "כחצות - Kachatzos." According to Rashi's first explanation, it means when it is divided; according to the second explanation, it means about halfway. However, in either case, Rashi is not explaining the word "night."

The Explanation

We will understand the answer to all of these questions by first explaining the unusual expression Rashi uses here. There are instances in which Rashi gives two explanations, one according to Peshat and the other according to a Midrash. Generally, after Rashi explains the answer according to Peshat, he will say something along the lines of "This is the explanation according to Peshat; however, our Sages said in a Midrash... "Here he says, "this is its simple meaning, which fits its context..." Our Rabbis, however, interpreted it as..." In this manner, Rashi clarified that the difficulty in the verse is neither because of the word חצות, nor because of the impossibility of saying that Hashem has any doubt. The difficulty Rashi is explaining is that the explanation according to Peshat must fit the verse's context.

When the beginning student learns this verse, the obvious question that immediately bothers him is: why did Hashem have to give a time when the plague will strike, unlike most of the previous nine plagues? Among the other nine plagues, there were only three that Hashem made known when they would take place. Namely, only the plagues of pestilence, hail, and locusts were given a specific time frame. Regarding pestilence and locusts, Hashem only told Pharaoh they would occur the next day. The only plague, besides the death of the firstborn, for which Hashem informed Pharaoh exactly when it would happen, was hail. The verse states, "I am going to rain down at this time tomorrow." Rashi comments there that Moshe "made a scratch on the wall (to show that) 'Tomorrow, when the sun reaches here, the hail will come down.'" However, there was a reason for that. It was to allow the Egyptians who feared G-d the opportunity to remove their livestock, etc., from the fields. Here, that reason does not apply at all.

By explaining "חצות - Chatzos," Hashem did not inform Pharaoh when the plague would occur. All that he knew was that it would take place at about midnight. Moshe never told him the day on which it would happen. This knowledge was seemingly useless to Pharaoh.

Therefore, we must say that the purpose of telling Pharaoh that the plague would take place at about midnight was not to let him know when to expect it. We must say that Moshe was giving a qualitative account of the plague. Saying that it would be "at approximately midnight" emphasized the fact that "I will go out," this plague will be performed by G-d Almighty Himself in His essence and His glory.

We need to understand how foretelling that the plague would occur at about midnight would help express that Hashem Himself would slay the firstborn. To the contrary, as mentioned above, Moshe demonstrated to Pharaoh that the plague of hail would be at the exact time that G-d promised. Here, on the other hand, Moshe told Pharaoh that it would be at about midnight! How could that help Pharaoh understand that this plague is coming directly from G-d!

To answer this question, Rashi begins by translating "כחצות - Kachatzos" as "when the night was divided." The moment that the night is divided in half is not a duration of time; it's not a second or a nanosecond. It cannot be measured in any way, shape, or form. If it were a measurable duration, it would be divisible as well. Only G-d Almighty Himself could determine this moment. That is how the words "כחצות הלילה – when the night is divided" demonstrate that Hashem Himself would go out into Mitzraim and destroy the firstborn.

However, we still need to explain why the Torah uses the word "כחצות - Kachatzos", which can be understood in two different ways. Not only does this make the meaning unclear, but to make his point, Rashi must bring proof from the Tanach. Moreover, one proof was insufficient; he needed to cite two proofs. It would have been much more transparent and understandable, according to Peshat, had the Torah said "בחצות – at midnight!"

Therefore, Rashi adds a second explanation that is not entirely consistent with Peshat (though it is consistent with the Midrash). According to the second explanation, Moshe began saying "So said Hashem" and concluded "at about midnight." However, even according to what our Rabbis said in a Midrash, "Hashem Who knows His times and His seconds (actually) said "at midnight." According to "Our Rabbis," this also makes the point that "I will go out in Mitzraim" – because otherwise there would have been no reason to assign a time to the plague (as explained above at length). However, since we do not find any mention of G-d telling Moshe one thing and then telling him to transmit it differently to Pharaoh, it is Midrashic rather than Peshat.

(Adapted from a talk given on Shabbos Parshas Bo and Yisro 5740)

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This also explains why Rashi also cites the word “הלילה – the night” in the heading, despite the fact that he only seems to be explaining the word “חצות – half.” By including the seemingly extra words, he emphasizes that unlike the plague of hail it was 1.) At night, so there was no way to make a scratch on the wall in order to see when the sun reaches it, and 2.) It was not at a particular second, but rather at an immeasurable moment of time.

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