There has been no Temple for almost 2,000 years. Why read its rules every morning?
The Gemara asks this question, and gives it to Avraham. He is afraid his descendants will sin and be wiped out like the generation of the Flood. God says no. Avraham asks how he can be sure, and God answers by pointing to offerings. Avraham pushes back: that works while the Temple stands. What will become of them when it does not?
God's answer: "I have already set out for them the order of the offerings. Whenever they read it, I count it for them as if they were bringing an offering before Me, and I forgive all their sins."
A second passage says something close. Rabbi Yitzchak notices that the Torah introduces these laws with the phrase "this is the torah of the sin offering." Torah means teaching. He concludes that whoever is busy with the teaching of an offering is counted as if he brought it. The note printed in your siddur just above this passage quotes him.
Two limits are worth knowing. First, both sources say "as if." Neither one says that reading is the same as a working Temple. Second, the same note in the siddur says that saying the verses is not enough. You are meant to think about what the offerings were for and how they worked, as far as you are able. The Mishnah Berurah (a central commentary on daily Jewish law, written around 1900) agrees: the Gemara means a person who works to understand the subject, not one who only says the words.
The sources also treat this as a custom. The Shulchan Aruch says it is "good to say" the offerings, and that "some have the custom" of beginning with the basin.
The Midrash Tanchuma (an early collection of rabbinic teachings on the Torah) tells the story of how the basin was made. Near its end the people say: "We have no Mishkan and no Temple. Let the prayer of our mouths be before You like the gifts to the Mishkan."
Megillah 31b (also Taanit 27b),Menachot 110a,Siddur Sefard, note before the offerings,Mishnah Berurah 48:1,Shulchan Aruch, Orach Chaim 1:5 and 1:9,Midrash Tanchuma, Pekudei 9The basin was made from makeup mirrors. Why would God want those in the Mishkan?
When the Mishkan was built, the Torah says the basin was made "from the mirrors of the women who gathered at the entrance of the Tent of Meeting." Three classic commentators read that verse three ways.
Rashi quotes the Midrash Tanchuma. Moshe wanted to reject the mirrors, because they were made for vanity and desire. God told him: "Accept them. These are dearer to Me than everything else." In Egypt the men were worn out by slave labor. Their wives would bring them food and drink, then hold up a mirror so that both faces showed, and tease: "I am better looking than you." That woke their husbands' desire, and that is how the next generation was born. In the Midrash itself Moshe is not just reluctant. He is furious.
Ibn Ezra reads the verse nearly the opposite way. It was normal, he says, for women to look in a mirror every morning. These women had turned away from the desires of this world. They no longer needed mirrors, so they gave them away, and they came to the Tent every day to pray and to hear the commandments.
The Ramban knows both readings and adds a plain one: the mirror copper was polished and beautiful, so it was set aside for this vessel, and women came in crowds to give. He also explains what bothered Moshe in the Midrash. Women's jewelry had already been accepted for the Mishkan, but it was mixed in with everything else. Here one whole vessel would be made from nothing but objects made for desire. Moshe would not choose that until God told him to.
So the commentators disagree about who these women were. On Rashi's reading, the gift Moshe thought least fit for the Mishkan was the one God valued most, and it became the basin where every kohen got ready to serve.
Shemot 38:8,Rashi on Shemot 38:8,Midrash Tanchuma, Pekudei 9,Ibn Ezra on Shemot 38:8,Ramban on Shemot 38:8It says they will die if they do not wash. Die, for skipping a hand washing?
The passage says it twice: they must wash, "and they will not die." Rashi spells out what that means: if they do not wash, they will die. The second mention, he says, covers a kohen serving at the altar in the courtyard, since the first was only about entering the Tent.
The Rambam states it as law. A kohen who served without washing his hands and feet that morning is liable to "death at the hands of Heaven," and his service does not count. Notice the wording. This is not a sentence that a court carries out. It is left to God.
Why so serious? It is not about how dirty he was. The Sefer HaChinukh (a book from Spain in the 1200s that explains each mitzvah) points out that a kohen had to wash even if he arrived completely clean, and that one washing in the morning covered him for the whole day. He concludes that the washing was there to magnify the honor of the House and of everything done in it.
The Ramban compares it to a palace. Anyone who serves at a king's table and touches the king's food washes his hands first, because hands get into everything. The kohanim served barefoot, he adds, so they washed their feet too. For the Ramban, washing is how you show honor to the One above. The Rambam puts the washing next to the kohen's special clothing. The Torah calls both "a law forever," and service done without either one is invalid.
The Torah itself gives no reason for the penalty. One way to put these explanations together: the washing was about honor. A kohen did not walk into God's house the way he would walk into any other room.
Shemot 30:20-21, with Rashi,Rambam, Laws of Entering the Temple 5:1-2,Sefer HaChinukh 106,Ramban on Shemot 30:19