MISHNA: Seven days prior to Yom Kippur the Sages would remove the High Priest, who performs the entire Yom Kippur service, from his house to the Chamber of Parhedrin, a room in the Temple designated specifically for the High Priest during that period. And they would designate another priest in his stead to replace him lest a disqualification due to impurity or another circumstance beyond his control prevent him from entering the Temple on Yom Kippur.

Rabbi Yehuda says: The Sages would even designate another wife for him lest his wife die, as it is stated in the Torah portion of the Yom Kippur service: “And it will atone for him and for his house” (Leviticus 16:6); the Sages interpreted the term: His house, that is his wife. The priest must be married in order to fulfill this commandment. Due to the concern lest his wife die, another wife was designated to address that possibility. The Rabbis said to Rabbi Yehuda: If so, that this is a concern, there is no end to the matter, as what if the designated replacement wife dies? This possibility need not be a source of concern.

GEMARA: The halakha of sequestering the High Priest prior to his performance of the Temple service on Yom Kippur is comparable to the sequestering of the priest designated to burn the red heifer. Therefore, the Gemara cites that which we learned in a mishna there, in tractate Para: Seven days prior to the burning of the red heifer, the Sages would remove the priest who burns the heifer from his house to the chamber that was before the bira at the northeast corner of the courtyard on the Temple Mount. And that chamber was called the Chamber of the Stone House. The Gemara explains: And why was it called the Chamber of the Stone House? It is because all the actions associated with the red heifer were performed in dung vessels, stone vessels, and earth vessels, which are vessels that cannot become ritually impure.

The Gemara asks: What is the reason that they were so stringent with regard to the purity of the heifer? The Gemara explains: It is since a priest who immersed that day is fit for service and may perform the ritual of the heifer after immersion, even before sunset, as we learned in a mishna: They would intentionally render the priest who burns the heifer ritually impure and immerse him immediately, to remove a misconception from the hearts of the Sadducees by means of a public display of disregard for their ruling. As the Sadducees would say: Only by those for whom the sun set was the heifer ritual performed. The Sadducees believed that it is prohibited for priests who began the purification process with immersion during that day to burn the red heifer until sunset, when the purification process is completed.

That mishna continues: Since they would intentionally render the priest who burned the heifer ritually impure, the Sages in turn instituted the stringencies of utilizing dung vessels, stone vessels, and earth vessels, which do not have the capacity to become ritually impure, lest people come to treat the ritual with contempt and perform it in ritual impurity after seeing that the red heifer ritual was performed by one who immersed that day.

Apropos the mishna in tractate Para, the Gemara asks: What is different about the chamber located in the northeast corner of the Temple courtyard that led the Sages to house the priest performing the red heifer ritual specifically in that chamber? The Gemara answers: It is different since it is a sin-offering, as the red heifer is referred to as a sin-offering in the Torah, and the slaughter and sprinkling of the blood of a sin-offering must be performed north of the altar; and since it is written with regard to the red heifer: “And sprinkle it before the opening of the Tent of Meeting” (Numbers 19:4), and before the Tent of Meeting means on its eastern side. Therefore, the Sages established a chamber in the northeast so that the ritual of the red heifer will have a distinctive indicator; this will cause the administering priest to be vigilant in its performance.

The Gemara asks with regard to the terminology of the mishna: What is the meaning of the term bira cited there? Rabba bar bar Ḥana said that Rabbi Yoḥanan said: There was a place on the Temple Mount and its name is bira, and the Chamber of the Stone House was adjacent to it. And Reish Lakish said: The entire Temple is called bira, as it is stated in the prayer of David: “To Solomon my son grant a wholesome heart, to observe your commandments, your admonitions, and your statutes, to fulfill them all, and to build the bira for which I have made provision” (I Chronicles 29:19).

§ With regard to the halakhot of sequestering the High Priest prior to performance of the Yom Kippur service, and of sequestering the priest designated to burn the heifer prior to performance of the red heifer ritual, the Gemara asks: From where in the Torah are these matters derived? Rav Minyomi bar Ḥilkiya said that Rabbi Maḥseya bar Idi said that Rabbi Yoḥanan said they are derived from Aaron and his sons, who remained in the Tabernacle for seven days prior to performing the service in the Tabernacle on the eighth day of their inauguration, as the verse states: “As has been done this day, so the Lord has commanded to do, to make atonement for you” (Leviticus 8:34), meaning that this mitzva of sequestering was not limited to the days prior to the dedication of the Tabernacle; rather, it applies to future generations as well. The verse is interpreted homiletically: “To do”; these are the actions performed in the burning of the red heifer for which the priest performing the ritual is sequestered seven days in advance; “to make atonement”; these are the actions performed on Yom Kippur, before which the High Priest is sequestered seven days.

The Gemara asks: Granted, the entire verse is not established as referring exclusively to the red heifer, as: “To atone,” is written, and the heifer is not capable of facilitating atonement; rather, it facilitates ritual purity. Rather, say that the entire verse is written with regard to Yom Kippur, as the rites performed to achieve atonement on Yom Kippur are similar to those performed during the days of the inauguration. What, then, is the source for sequestering the priest who is to perform the red heifer ritual?

The Sages say in response: Derive it from a verbal analogy between the terms commanded and commanded. It is stated here, with regard to the days of the inauguration: “The Lord commanded to do,” and it is stated there, with regard to the red heifer: “This is the statute of the Torah that the Lord commanded, saying” (Numbers 19:2). Just as the term commanded there refers to the heifer, so too here, the phrase: “The Lord commanded to do” written in the context of the days of the inauguration refers to the heifer. And just as here, with regard to the inauguration, there is the principle of sequestering prior to performing the service, so too there, in the context of the halakhot of the heifer, sequestering is required prior to performance of the mitzva.