The Priestly Watches and Stations
These are the ma‘amadot, as it says: Command the Israelite people and say to them: “My sacrifice, My bread” (Numbers 28:2). How is a person’s sacrifice brought without him standing over it? The first prophets established twenty-four watches. Over each and every watch was a ma‘amad in Jerusalem of priests, Levites, and Israelites. When the time arrived for the watch to ascend, the priests and Levites would ascend to Jerusalem, and the Israelites who were part of that watch would gather in their cities and read the [biblical passage] about the work of creation.
Published in: The Posen Library of Jewish Culture and Civilization, vol. 2: Emerging Judaism.