In the synagogue the Torah is read aloud in a fixed annual cycle of fifty-four weekly portions (parashiyot), one each Shabbat morning, with certain adjacent portions doubled in ordinary years so the sequence fits the calendar. Each portion is named for a distinctive word near its opening and is paired with a haftarah, a reading from the Prophets. The cycle closes and restarts on Simchat Torah. Bamidbar ('In the Wilderness', Numbers 1:1-4:20) opens the book of Numbers with a census of the twelve tribes, the arrangement of the camp around the Tabernacle, and the special role of the Levites. It is customarily read on the Shabbat before Shavuot.
The census that opens Numbers, counting only males twenty and older able to bear arms (Numbers 1:2-3), is read by rabbinic commentary as organising the people not merely for religious life but as a military and administrative structure preparing for the conquest of Canaan, distinguishing this numbering from the earlier half-shekel census in Ki Tisa, which served a different, atonement-related purpose. The Levites' distinct census, counted separately from one month old rather than twenty years, and their assignment to encircle and transport the Tabernacle rather than serve in the army (Numbers 1:47-53, 3:14-39), is read by commentators as establishing their unique status as a tribe set apart for sacred rather than martial duty from the outset of nationhood. The custom of reading Bamidbar on the Shabbat before Shavuot is explained by commentators as fitting, since the wilderness setting of the census recalls the same wilderness location where the Torah itself was given, read as teaching that revelation was granted in an ownerless, open wilderness rather than in any single tribe's territory.