Recent research has shown that sitting for long periods of time is linked to increased risk of heart disease, cancer and metabolic syndrome. On today’s daf, the rabbis discuss another unanticipated risk of extended sitting: The ritual disqualification of sacrifices.
The mishnah on Zevachim 15b taught that a priest must be standing when offering a sacrifice. If he performs any of the actions of sacrifice while seated, the sacrifice is disqualified. Today’s daf follows the rhythm we’ve seen in the most recent pages, beginning by exploring the biblical source of this rule and then interrogating how it fits with other rabbinic traditions.
From where do we derive this? Rava says that Rav Nahman says: The verse states: “For the Lord your God has chosen him out of all your tribes, to stand to minister.” (Deuteronomy 18:5). I have chosen him for standing and not for sitting.
In Deuteronomy 18, Moses addresses the Levites and the priests in preparation for entering the land of Israel. Deuteronomy 18:5 contains a strange doubled set of infinitives: la’amod le-sharet, “to stand to minister.” The verb “to stand” seems redundant, so Rav Nahman reads it as coming to teach us this particular detail about the priestly service – that it must be done standing. The Talmud then cites a beraita which breaks down the source of this mishnaic rule into two parts.
The sages taught: “To stand to minister,” a mitzvah. When it says: “Then he shall minister in the name of the Lord his God, as all his brethren the Levites do, who stand there before the Lord” (Deuteronomy 18:7), the verse repeats to invalidate.
According to the beraita, Deuteronomy 18:5 teaches us that it is a mitzvah to stand while performing sacrifices. But just because something is a mitzvah, that doesn’t mean that if you don’t do it, everythingyou do is disqualified. There are lots of things we are supposed to do, but if we don’t, this doesn’t invalidate other things we are doing. The distinction is captured in two rabbinic terms: le’chatchila (in Latin, a priori), the way things are supposed to be done, and bedieved (a posteriori), the ways that things can be done and still count, at least post facto. So to prove that standing to perform the sacrifice is not just a mitzvah but in fact is necessary for the sacrifice to count, the rabbis then turn to another verse, which repeats the command to stand. This repetition, they say, is our proof that sitting disqualifies the sacrifice.
The Talmud next asks some important follow-up questions:
Rava said to Rav Nahman: Now, one who is sitting is considered like a non-priest and desecrates the service. Therefore, I will say: Just as a non-priest is to receive death, so too one who is sitting should be liable to receive death. If so, why is it taught: But one who is uncircumcised, an acute mourner, and one who is sitting are not to receive death; rather, (they simply transgress) a prohibition?
That escalated fast. If a sitting priest offering a sacrifice is tantamount to a non-priest offering a sacrifice, should the former be punishable by death, since the latter is a capital offense? No. Rava knows of another beraita that explicitly states that a priest who performs a sacrifice while sitting is liable for transgressing a prohibition, but is not punished by death.
On the top of tomorrow’s daf, the Talmud will explain that a particularly close reading of the relevant biblical verses demonstrates that sitting is excluded from the punishment of death. But while the sitting priest does not die, the sitter is still punished for their transgression and the sacrifice is still invalid.
Priestly service was difficult physical labor. A priest needed to have a strong core for stability and excellent leg muscles and glutes to keep himself upright during long shifts at the Temple. And remember, priests served barefoot, which meant that foot strength was also key. So if you’re a member of the priestly tribe and eagerly anticipating a third Temple, you’d better start working out now.
Read all of Zevachim 23 on Sefaria.
This piece originally appeared in a My Jewish Learning Daf Yomi email newsletter sent on October 7, 2025. If you are interested in receiving the newsletter, sign up here.
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