The Gemara asks: If so, then just as a priest who ministers in the Temple may not be physically blemished, so too, a priest who recites the benediction may not be blemished. The Gemara rejects this suggestion: The priest who recites the benediction is also juxtaposed to a nazirite, who is not affected by a blemish.

The Gemara asks: And what did you see that you juxtaposed the cases in favor of a leniency? Perhaps you should juxtapose for a stringency, by comparing the priest who recites the benediction to a nazirite with regard to grape pits, and comparing him to a priest ministering in the Temple in relation to the prohibition against reciting the benediction if he has a physical blemish. The Gemara explains: These proofs are cited merely as support for halakhot that apply by rabbinic law, and consequently, they are interpreted as a leniency, not a stringency.

§ The mishna taught that these are the non-priestly watches: Since it is stated: “Command the children of Israel.” The Gemara asks: What is the mishna saying about the non-priestly watches? How does the verse relate to the watches? The Gemara explains that the mishna is saying as follows: These are the non-priestly watches, which will be explained later. And what is the reason that they instituted non-priestly watches? Since it is stated: “Command the children of Israel and say to them: My offering of food, which is presented to Me made by a fire, of a sweet savor to Me, you shall observe to sacrifice to Me in their due season” (Numbers 28:2).

The mishna continues: But how can a person’s offering be sacrificed when he is not standing next to it? The early prophets, Samuel and David, instituted twenty-four priestly watches. For each and every priestly watch there was a corresponding watch in Jerusalem of priests, Levites, and Israelites. When the time arrived for the members of a certain priestly watch to ascend, the priests and Levites of that watch would ascend to Jerusalem.

The Sages taught: There were twenty-four priestly watches in Eretz Yisrael, and twelve in Jericho. The Gemara expresses surprise at this statement: Twelve in Jericho? In that case there are too many of them, as this makes a total of thirty-six watches. Rather, the baraita should be read as follows: There were twenty-four in total, twelve of which were in Jericho. How so? When the time arrived for the members of a certain priestly watch to ascend, half the priestly watch would ascend from all over Eretz Yisrael to Jerusalem, and half the priestly watch would ascend from Jericho, in order to provide water and food to their brothers in Jerusalem from Jericho.

Rav Yehuda said that Shmuel said: Priests, Levites, and Israelites are all indispensable for the offering, and consequently, they all must be present when the daily offering is sacrificed. It is taught in a baraita that Rabbi Shimon ben Elazar says: Priests, Levites, and musical instruments are indispensable for the offering. The Gemara asks: With regard to what principle do they disagree? One Sage, Shmuel, holds that the main aspect of the Levites’ song that accompanied the offerings is vocal, and one Sage, Rabbi Shimon ben Elazar, holds that the main aspect of their song is instrumental, performed with a vessel, and therefore both the Levites and their instruments must be present for the daily offering.

Rav Ḥama bar Gurya said that Rav said: Moses initially instituted for the Jews eight priestly watches, four from the descendants of Elazar and four from the descendants of Itamar. Samuel came and established them as sixteen, and David came and established them as twenty-four, as it is stated, after the watches are listed: “In the fortieth year of the reign of David they were sought for, and there were found among them mighty men of valor at Jazer of Gilead” (I Chronicles 26:31).

The Gemara raises an objection against this opinion from a baraita. Moses instituted for the Jews eight priestly watches, four from Elazar and four from Itamar. And David and Samuel came and established them as twenty-four, as it is stated: “Whom David and Samuel the seer ordained in their set office” (I Chronicles 9:22). This baraita indicates that David and Samuel together established the twenty-four watches. The Gemara explains: This is what the baraita is saying: Through their ordination by David and Samuel of Rama the priestly watches incrementally increased in number until they established them as twenty-four.

It is taught in another baraita: Moses instituted for the Jews sixteen priestly watches, eight from Elazar and eight from Itamar. And when the descendants of Elazar grew more numerous than the descendants of Itamar, he divided the descendants of Elazar and established them together with the descendants of Itamar as twenty-four watches, as it is stated: “And there were more chief men found of the sons of Elazar than of the sons of Itamar, and they were divided thus: Of the sons of Elazar there were sixteen heads of fathers’ houses, and of the sons of Itamar, according to their fathers’ houses, eight” (I Chronicles 24:4). And it says: “One father’s house taken for Elazar, and proportionately for Itamar” (I Chronicles 24:6).

The Gemara asks: What is: And it says? Why was it necessary to quote a second verse? The Gemara explains: And if you would say that just as the descendants of Elazar increased, so too, the descendants of Itamar increased, and the eight watches were initially four, as claimed by Rav Ḥama bar Gurya, then come and hear: “One father’s house taken for Elazar, and proportionately for Itamar,” which indicates that the descendants of Itamar remained as they were. This verse is apparently a conclusive refutation of the opinion of Rav Ḥama bar Gurya, who says that Moses established only eight priestly watches.

The Gemara responds: Rav Ḥama bar Gurya could have said to you that the initial order of the priestly watches is a dispute between tanna’im, as indicated by the previous baraita, and I stated my opinion in accordance with that tanna who said that Moses instituted eight priestly watches.

The Sages taught: Only four priestly watches ascended from the Babylonian exile, while the other twenty stayed in Babylonia. And these are the watches who returned: The descendants of Jedaiah, Harim, Pashhur, and Immer. The prophets among those who returned arose