Separation by lamb blood
החדש הזה לכם ראש חדשים ראשון הוא לכם לחדשי השנה: דברו וגו’ ויקחו להם איש שה לבית-אבת שה לבית: ואם-ימעט הבית מהית משה ולקח הוא ושכנו הקרב אל-ביתו וגו’ ולקחו מן-הדם ונתנו על-שתי המזוזת ועל-המשקוף על הבתים אשר-יאכלו אתו בהם: והיה הדם לכם לאת על הבתים אשר אתם שם וגו’ ואתם לא תצאו איש מפתח-ביתו עד-בקר: ועבר יקוק לנגף את-מצרים וראה את-הדם על-המשקוף וגו’ ולא יתן המשחית לבא אל-בתיכם לנגף
This month will be for you the beginning of the months; for you it is the first for the months of the year. Tell [the Jewish people that]…they will take for them, each man, a lamb for the fathers’ homes, a lamb for each household. If the lamb will not suffice for the household, they and the neighbor close to their house will take…Take from the blood and place it on the two doorposts, and the lintel of the house that you will eat [the offering] in. The blood will be for you a sign on your houses that you will be in…and you shall not leave, each person, from the door of their house, until morning. Hashem will pass by to afflict the Egyptians, and will see the blood on the lintel…and He will not let the Destroyer come to your houses to afflict
Before the plague of the death of the firstborn, Moshe instructed the Jews with several mitzvos. He started by informing them about the Jewish calendar, in which Nissan is the first of the months. This included details of the mitzvah to sanctify the New Moon, establishing the months accordingly. Subsequently, he informed them of the mitzvah of the Pesach offering. This included instructions on selecting a lamb for each household, taking its blood and putting it on the doorposts, and staying indoors until morning. How are we to understand the juxtaposition of these two mitzvos? As well, upon careful examination, we’ll observe that the first mitzvah given to the Jewish people as a whole is the mitzvah to sanctify the New Moon. Why was this mitzvah held in such high esteem that it merited to get the position as the first mitzvah? Finally, with regards to the Pesach offering, why is there so much emphasis on the house? It’s repeated and stressed multiple times. What could be the reason?
There’s a Midrash which compares the extraction of the Jewish people from Egypt to someone removing a developing fetus from the animal’s womb. The Jewish people were considered enclosed in the womb of Egypt. This is evident from the fact that the Jews were uncircumcised, as were the Egyptians. The Jews had idol worshipping practices, as did the Egyptians. What this symbolizes is that the Jews were totally and entirely connected to Egyptian society, like a fetus to the womb. Normally, a baby isn’t assisted in being born until it is developed enough to survive. Otherwise, there’s a danger of a loss to the baby. So too the Jewish people. Their connection to the Egyptians was so strong that it would have been dangerous to remove them at that point. Physically they looked similar, as they were both uncircumcised. In their behavior they were similar in that they both had idol worshipping practices.
To ensure their safe removal from Egypt, Hashem had to remove any ties the Jews had to the Egyptians. First and foremost, He commanded them to separate from idol worship. Then, he commanded them to circumcise themselves. This way they would be different in mind and in body. This was Hashem’s intent with the mitzvah of the Pesach offering. The offering was a lamb, which was the idol of the Egyptians, and it was an animal the Jews worshipped as well. The procedure of the offering was to perform an action which would uproot from their hearts and minds the ideology of the Egyptians.
They would roast the Pesach offering, and its scent would spread throughout Egypt. The Egyptians would either become mortified by their deity being roasted, or they would be tempted to join in the feast. Those that would want to join would be rejected. A specific mitzvah was given that the Pesach offering could only be eaten by Jews, not given to non-Jews for consumption. The Jews were told to spread its blood on their doorposts, so that the Egyptians would see their deity being defiled. They’ll run away and disassociate from the Jews. To stop a Jew from running outside to invite them in, Hashem commanded that no one that evening may leave from their homes. All of this was to prevent any interaction, comradery, or association between the Jews and the Egyptians.
Besides the preparation of the Pesach offering, and the way it was eaten, even the Jews’ houses created a distance between them and the Egyptians. Even though the Jews and the Egyptians lived side by side, the Jewish homes became distinguishable. The noticeable lamb blood smeared on the doorposts made it clear which homes belonged to the Jews. So long as the doors to the Jewish home were open to the Egyptians, and vice versa, there was no hope to prevent their interaction. Hashem commanded all of these mitzvos at this time, to so-to-speak, start the birthing process. He did this to subsequently remove the baby of the Jewish people from the womb of Egypt. A successful birth would only be possible by separating the two completely. This is why the Torah keeps stressing the houses of the Jews. All of these mitzvos were meant to create a separation between these incompatible societies. This was taken so far that even the Jewish houses were different.
With this, we can now understand the connection to the first mitzvah and the Pesach offering. The Jews were commanded to count their months starting from Nissan. Why was this chosen as the first mitzvah? Let’s examine the Jewish calendar for a moment. It follows the lunar cycle. The Moon, as is evident to all, does not generate its own light. It reflects the light it receives from the Sun. How much light it reflects depends on its position. When the Moon is the farthest away from the Sun, that’s when it has the most light. When it’s the closest to the Sun, that’s when it’s a New Moon, and is completely invisible.
This can all be seen as a parable for the Jewish people, who count their calendar according to the Moon. The Jews’ greatness, represented by the light of the Moon, is only when they are as distant as possible from the idol worshipping Egyptians, represented by the Sun. The closer they are, the dimmer the Jews’ light. Now everything makes sense. All the mitzvos of the Pesach offering had the intent to distance the Jews from the Egyptians. This is why these mitzvos are introduced with the mitzvah of sanctifying the New Moon. Both have the same message and purpose. This is also why the mitzvah of sanctifying the New Moon was given first. It was to implant within the Jewish people the understanding that they are to be as distant from idol worship as possible. Only then will they have any success.
 Based on Be’er Yosef to Exodus 12:2,3, 7, 13, 22, 23
 Exodus loc. cit.
 Mechilta to Exodus 14:30; Midrash Tehillim 114:3 (brought in Yalkut Shimoni § 828). See also Mechilta D’Rashbi to Exodus 14:28
 Midrash Tehillim loc. cit.
 Vayikra Rabbah 23:2, Pesikta D’Rav Kehannah 5:11, and Pesikta Rabbasi § 15 (brought in Yalkut Shimoni loc. cit.)
 See Exodus 12:43 and Mishneh Torah Hilchos Korbon Pesach 9:7 and Kesef Mishnah ad. loc.
 See Mechilta to Exodus 12:7, which brings a dispute if the blood was visible to the outside, or if it was smeared on the inside of the doorposts. The Be’er Yosef is using the former opinion, whereas Rashi ad. loc. v. 13 brings the latter
 What’s not clear is that many of the details of the Pesach offering apply today, even after the Exodus from Egypt. Why were they commanded for all time if they were for a specific purpose during the Exodus?
 The Be’er Yosef brings the following analysis from the sefer Beis Dovid Derush LeYomei Nissan, by the author of Nachalas Dovid
 See Chullin 60b, which describes how originally the Moon generated its own light
 The Jews are compared to the Moon in many sources. For example, see Sukkah 29a
 See the Be’er Yosef, who focuses on material success in this world. That is primarily designated for the non-Jews, which is why they are represented by the Sun. The Jews’ success in this area is merely a reflection of that