Who we are

The following is from a drasha by R' Yehoshua Hartman, adapted from the Maharal.

וַיֵּלְכוּ וַיַּעֲשׂוּ בְּנֵי יִשְׂרָאֵל כַּאֲשֶׁר צִוָּה ה' אֶת מֹשֶׁה וְאַהֲרֹן כֵּן עָשׂוּ - So the children of Israel went and did; as the Lord commanded Moses and Aaron, so they did. (12:28)

כאשר צוה ה' את משה ואהרן: להגיד שבחן של ישראל, שלא הפילו דבר מכל מצות משה ואהרן. ומהו כן עשו? אף משה ואהרן כן עשו - as the Lord commanded Moses and Aaron [This comes] to tell Israel’s praise, that they did not omit anything of all the commandments of Moses and Aaron. And what is the meaning of “so they did” ? Moses and Aaron also did so. (Rashi)

It is quite perplexing as to why the Torah would insert כֵּן עָשׂוּ, talking about Moshe and Ahron, as on what grounds might we have thought that they might not perform the Mitzva of Korban Pesach? This is illogical, as the Pasuk doesn't specify whether or not they kept Shabbos, yet does here.

Additionally, why by this 10th plague is human input necessary? The first nine did not affect Jews in the slightest. By the first plague for example, blood, even a Jew drinking from the same cup as an Egyptian with straws would not be affected, whereas the Egyptian would. Why by the final plague is there a requirement to partake and perform this Mitzva and smear the door posts and lintel in order to be saved?

Furthermore, the Korban Pesach was not the only Mitzva given on the night they set aside the goats, circumcision was instituted that night too. What is particularly special about these two mitzvos that they needed to be instructed to perform them on the night of the Slaying of the Firstborn?

It says in Ezekiel (16:4) that the Jewish People were born in Egypt. There are two aspects of the Jewish People - the doing, and the being.

Every person born to a Jewish mother is a Jew from the moment they open their eyes unitl the moment they close them. This is the being aspect. There is not a thing that can change this. People can convert and practice other religions, but halacha states that they remain Jews. There is no free will in the matter. The reason for this is simple. G-d chose us, and there is nothing anyone can do about that. This is simple to understand: just as you can't change your friend's decision, how much more so are you powerless to change G-d's decisions?

The second aspect, of doing, is much more down to personal choice, to do as we were commanded.

Bris Milah is a Mitzva of being - it is performed 8 days after a boy is born and they have no say in the matter. It is G-d's sign on our flesh, and cannot be undone. Korban Pesach is a personal choice (though not a great one as those who didn't do it died...). It is the only Mitzva in the entire Torah where the word עבודה, service, is used. Interestinly, these are the only two positive commandments who's punishment for not performing them is Kareis, spiritual excommunication.

This is why these Mitzvot were given, at the time that the Jewish People were born. They gave us our identity, of being and acting as Jews. This answers the final question.

So why did the Jews have to work to be saved from the 10th plague? As Hashem performed it Himself. Whereas with the other 9, angels and messengers were used, are unable to harm Jews as Jews are on a higher spiritual level than angels, and as such were unable harm the Children of Israel. But Hashem is above this instruction; He is above everything! He was looking for people to actually bind themselves to Him through the Mitzvos Hegave them; it wasn't like the other 9 where it had been enough to be born to a Jew. They had to demonstrably show they were on G-d's "side" to be saved.

With this in mind, we can answer the first question. If people had to prove they were with G-d, you'd have thought that being G-d's mouthpiece to Egypt and the Jews was enough for Moses and Ahron, they'd shown who their lot was cast with. This is inaccurate. The doing/being aspect has another paralel, to a servant for example. A servant has to serve, and his service is proven by the fact that he serves 24/7. Moses and Ahron were not servants, as they only did what G-d asked them when they were asked, but it was only a 9 to 5 job, so to speak, but whenever they weren't in His service, they were just normal people. So the pasuk said כֵּן עָשׂוּ to explain that actually, Moshe and Ahron also performed the Mitzva, and they too only became servants, עבדים of G-d after performing the עבודה of the Korban Pesach.

The doing/being has another relevancy to us. The mitzvot of Tfilin וּקְשַׁרְתָּם לְאוֹת עַל-יָדֶךָ וְהָיוּ לְטֹטָפֹת בֵּין עֵינֶיךָ And thou shalt bind them for a sign upon thy hand, and they shall be for frontlets between thine eyes. The brachos we make show this, one is "lehaniach" - on the binding, one is "al mitzvas" - passive, on the mitzva. This is further shown in the fact that if one puts on Tefilin before sunrise, one must retie the arm Tefilin to make the bracha, but does not need to adjust the head Tefilin. The reason for this is that our arms are what we use to do, so they must be active, and perform actions. Our heads are passive, our minds are who we are, and as such no new bracha is required.