He will provide atonement for you, to purify you.
Meshech Chochmah: Several times in the course of Yom Kippur we employ an unusual refrain in our davening. “You are the forgiver of Yisrael, and the pardoner of the tribes of Yeshurun.” The reference to “tribes of Yeshurun” is unparalleled in our liturgy.
We are accustomed to the idea of banishing gold from the avodah / service on Yom Kippur that took place in the Holy of Holies. From within this avodah, and in this specific place, came the forgiveness and atonement sought so desperately by a nation eager to reestablish its closeness with its Creator. According to R. Levi, for this reason the Kohen Gadol did not don his regal gold garments in the Kodesh Kodashim – Hashem had stated from the outset that He would not destroy the people because of the sin of the eigel/ Golden Calf, but would visit the punishment upon them in installments. Each generations receives some small measure of punishment for that early national failure. Another way of looking at this is that the sin of the eigel was never purged from the Jewish people; its fault line still runs through our national neshamah. It would be inappropriate and presumptuous to perform the key avodah asking for forgiveness while flaunting a symbol of a national failing that we have still not adequately addressed!
All this is familiar to us. Less known is the similar thinking regarding a different national shortcoming – the sale of Yosef into slavery. A midrash states that this aveirah as well persists through all generations. Calling attention to it at the most crucial juncture of the Yom Kippur avodah is as inappropriate as dressing for it in the gold that is symbolic of the eigel. (On the other hand, when we send away the goat to the wilderness, which symbolizes our distancing ourselves from aveirah, the goat bears a reference to the tragic sale of Yosef. The length of red wool that was attached to it weighed two sela’im, recalling the special coat of the same weight that Yaakov gave to Yosef. According to the gemara, the jealously provoked in the brothers through this showing preference for one brother among the others led to the sale of Yosef, and the subsequent descent of the rest of the family to Egypt and into servitude.)
Keeping this principle in mind, we can understand why the Holy of Holies – the location of the yearly atonement-service – stood in the portion of the Land allotted to the tribe of Binyamin. Alone among the shevatim, he was not involved in Yosef’s sale. While the lion’s share of the Temple area (the ascent of the Temple mount and the courtyards) stood in Yehudah’s portion, the building structure (including the Kodesh Kodashim) belonged to Binyamin. The avodah of atonement had to be linked to a space free of the taint of the sin of internecine strife between brothers. As Chazal put it, the prayers of those who showed no compassion to their brother would not be answered with Divine compassion.
G-d says that he “visits the sins of the fathers upon the sons;” Chazal interpret this as applying narrowly to sons who persist in the ways of their forbears. Putting all we have said together, when we continue sinning against G-d, He visits the sin of the eigel upon us. When we transgress laws of proper behavior to our fellow Jew, we are punished for the sin of Yosef’s sale.
For this reason, the Kohen Gadol / High Priest did not wear the choshen/ breastplate into the Kodesh Kodashim. The choshen bore the names of the twelve shevatim/ tribes. Sporting those names pointed an accusatory finger at the people for their continued practice of brother-against-brother sin. (This also accounts for the opinion of Rav Huna that the Urim V’Tumim ceased functioning after the times of Dovid and Shlomoh. After their deaths, the people divided into two kingdoms, with ten tribes in the northern kingdom, and Yehudah and Binyamin left in the other. The Divine messages received through the Urim V’Tumim folded within the choshen came by way of the various stones lighting up in sequence. By combining the letters of each stone – each identified with a different shevet – the message could be unscrambled and discerned. But how could the letters of the different stones combine with each other, when the tribes they represented were plagued with dissension, and could not join together!)
We have arrived at the answer to our opening question. Standing before Hashem each Yom Kippur, we pray for kapparah/ atonement. We are conscious of transgressions we committed against Him. For these we daven that He should forgive Yisrael. (All those aveiros still stem from the unextinguished sin of the eigel. There, those dancing around it said, “These are your gods, Yisrael.” And after Moshe’s invervention, Hashem responded, “I have forgiven them, according to your words.”
We also stand under the weight of many transgressions against our fellow Jew. For those we pray that He should pardon “the tribes of Yeshurun,” recalling that these shortcomings are tributaries of the first such sin – the sale of Yosef by the shevatim.
 Based on Meshech Chochmah, Vayikra 16:30
 Yerushalmi Yoma 3:3
 Shochar Tov, Mishlei 1
 Shabbos 10B
 Sifrei, Zos HaBerachah 12
 Shemos 34:7
 Sanhedrin 27B
 Sotah 48A
 Shemos 32:4
 Bamidbar 14:20