Midrash su Levitico 21:12

5) (Vayikra 21:12) ("And from the sanctuary he shall not go out, and he shall not profane the sanctuary of his G d; for the crown of the anointing oil of his G d is upon him, I am the L–rd.") "And from the sanctuary he shall not go out": He does not go out (i.e., he does not follow the litter), but follows after them, when they (the litter bearers) are concealed" (in an alleyway), he is revealed." When they are concealed (in a second alleyway), he is revealed. And he goes out with them until the entrance of the city. These are the words of R. Meir. R. Yehudah says: "And from the sanctuary he shall not go out": He does not go out at all.

6) And when is it derived that if he performed the (sacrificial) service (and does not go out after the hearse), it is valid? From "And (if he does not go out after the hearse) he does not profane the sanctuary of his G d." But if an ordinary Cohein serves while in mourning, his service is invalid. "for the crown of the anointing oil of his G d is upon him": This tells me (that he may not go out) only if he is anointed with the oil of anointment. Whence is the same derived for one who is clothed in the many vestments (of the high-priest)? From "for the crown of the anointing oil of his G d is upon him": This (i.e., the "crown" of the high-priesthood [the many vestments, along with the anointing oil] is the cause (of his not going out).

Rabbi Berachiyah said in the name of Rabbi Abbah Bar Kahana expounding on the verse about Aaron. At the time when the Israelites were about to commit the act [make the golden calf] they first came to Chur, and they said to him: "Make us a god!" Since he did not listen to them, they rose up and slew him. This is why it's later written in the prophets: "Also in your wings we find the blood of the souls of the innocent and the poor etc." This refers to the blood of Chur. . . . " Afterwards, they went to Aaron and said to him: "Make us a god." Aaaron had heard about what they did to Chur, and became afraid. It is therefore written: "Aaron was frightened and built an alter before them." Aaron was frightened that he might be the one who was going to be slaughtered. Aaron said, what should I do? They've already killed Chur, and he was was a prophet. Now if they kill me, the priest, they will fulfill the word later written in scripture: "Should priest and prophet be slain in the sanctuary of YHWH (Eicha 2:20)." If they kill me, they will all be exiled. Here is another interpretation (Davar Acher): Aaron saw this, and built an altar before it (Exodus 32:5). What did he see? He saw the situation playing out like this: If they build it, one will bring a pebble, another a larger stone, and they will finish the building of the idol in one day. If I build it, then I can delay and dally, and give time for our teacher Moses to come down the mountain and then destroy this idol worship. And if I build it, I can dedicate it to the name of the Holy one Blessed be God, therefore it is written: "Aaron called and said this shall be a festival for YHWH." It is not written a feast for the calf, but a feast to YHWH. Another interpretation: "And Aaron saw this, etc." What did he see? He saw the situation playing out as follows: "If they build it the sin will be upon them, but if it will be better if I build it, so that the sin should be upon me and not the people. Rabbi Abba Bar Yodan said in the name of Abbah, we can give a parable that demonstrates this. It's like the son of a king who became filled with pride in his heart and took a sword and rose up to try and cut his father. The son's tutor said to him: Don't trouble yourself, leave it to me and i'll do cut him for you." The king saw the tutor and said to him: "I know what your intention was, it was that you believed it better that the sin should be upon you than upon my son. As you live, you shall not leave my palace, and that which remains over from my table, you shall eat it, and you will receive twenty four perks. So too with Aaron: "You shall not leave my palace" is compared to "He shall not go out of the sanctuary Leviticus 21:12"And that which remains of the table, you shall eat it" is compared to: "That which is let of the meal-offering shall be Aaron's and his sons (Leviticus 2:3)." The twenty four perks is paralleled to the twenty four gifts of the priesthood assigned to Aaron and his sons. . . .