Most commentators divide Numbers into three sections based on locale (Mount Sinai, Kadesh-Barnea and the plains of Moab), linked by two travel sections;^[7] an alternative is to see it as structured around the two generations of those condemned to die in the wilderness and the new generation who will enter Canaan, making a theological distinction between the disobedience of the first generation and the obedience of the second.^[8]

God orders Moses, in the wilderness of Sinai, to number those able to bear arms—of all the men twenty years and older and to appoint princes over each tribe. A total of 603,550 Israelites are found to be fit for military service. The tribe of Levi is exempted from military service and therefore not included in the census. Moses consecrates the Levites for the service of the Tabernacle in the place of the first-born sons, who hitherto had performed that service. The Levites are divided into three families, the Gershonites, the Kohathites, and the Merarites, each under a chief. The Kohathites were headed by Eleazar, son of Aaron, while the Gershonites and Merarites were headed by Aaron's other son, Ithamar. Preparations are then made for resuming the march to the Promised Land. Various ordinances and laws are decreed.

The Israelites set out from Sinai. The people murmur against God and are punished by fire; Moses complains of their stubbornness and God orders him to choose seventy elders to assist him in the government of the people. Miriam and Aaron insult Moses at Hazeroth, which angers God; Miriam is punished with leprosy and is shut out of camp for seven days, at the end of which the Israelites proceed to the desert of Paran on the border of Canaan. Twelve spies are sent out into Canaan and come back to report to Moses. Joshua and Caleb, two of the spies, report that the land is abundant and is "flowing with milk and honey", but the other spies say that it is inhabited by giants, and the Israelites refuse to enter the land. Yahweh decrees that the Israelites will be punished for their loss of faith by having to wander in the wilderness for 40 years.

God orders Moses to make plates to cover the altar. The children of Israel murmur against Moses and Aaron on account of the destruction of Korah's men and are stricken with the plague, with 14,700 perishing. Aaron and his family are declared by God to be responsible for any iniquity committed in connection with the sanctuary. The Levites are again appointed to help in the keeping of the Tabernacle. The Levites are ordered to surrender to the priests a part of the tithes taken to them.

Miriam dies at Kadesh Barnea and the Israelites set out for Moab, on Canaan's eastern border. The Israelites blame Moses for the lack of water. Moses is ordered by God to speak to a rock but initially disobeys, and is punished by the announcement that he shall not enter Canaan. The king of Edom refuses permission to pass through his land and they go around it. Aaron dies on Mount Hor. The Israelites are bitten by fiery flying serpents for speaking against God and Moses. A brazen serpent is made to ward off these serpents.

The Israelites arrive on the plains of Moab, across the River Jordan from Jericho. Here, the Israelites find themselves in conflict with the Amorites and Og, king of Bashan, both of whom they defeat. Balak, king of Moab, decides to fight the Israelites as well, and summons a local diviner named Balaam to curse the Israelites. However, God tells Balaam not to curse them, and when Balaam attempts to travel to Balak with the Moabite officials God sends an angel to stop his donkey. Realising that he cannot curse the Israelites, Balaam blesses them instead, and foresees a figure whom he identifies as 'the Star of Jacob' who will defeat Israel's enemies. This angers Balak, but Balaam informs Balak that he cannot say anything except what God tells him to say.

The longer the Israelites stay on the plains of Shittim, the more they intermarry with the local Moabites, and the more they participate in the local religion, worshipping a deity known as Baal-Peor. God sends a plague in retaliation, and Moses tells the judges to kill anyone participating in this practice. When one of Aaron's grandsons, Phinehas, finds out a Simeonite prince named Zimri has married a Midianite woman named Cozbi, he enters their tent and runs a spear through them. God rewards him by giving his descendants an everlasting priesthood. God also tells the Israelites to consider the Midianites their enemies.

A new census gives the total number of men from twenty years and upward as 601,730, and the number of the Levites from the age of one month and upward as 23,000. The land shall be divided by lot. The daughters of Zelophehad, who had no sons, are to share in the allotment. God orders Moses to appoint Joshua as his successor. Prescriptions for the observance of the feasts and the offerings for different occasions are enumerated. Moses orders the Israelites to massacre the people of Midian, in retaliation for the Baal-Peor incident. Specifically, all Midianite men and boys and women who are not virgins are killed. Virgin Midianite women and girls are kept alive, counted, and distributed as prizes, along with the sheep, cattle and donkeys, to the officers of the Israelite army.

The Reubenites and the Gadites request Moses to assign them the land east of the Jordan. Moses grants their request after they promise to help in the conquest of the land west of the Jordan. The land east of the Jordan is divided among the tribes of Reuben, Gad, and the half-tribe of Manasseh. Moses recalls the stations at which the Israelites halted during their forty years' wanderings and instructs the Israelites to exterminate the Canaanites and destroy their idols. The boundaries of the land are spelled out; the land is to be divided under the supervision of Eleazar, Joshua, and twelve princes, one of each tribe.

The majority of modern biblical scholars believe that the Torah—the books of Genesis, Exodus, Leviticus, Numbers, and Deuteronomy—reached its present form in the post-Exilic period (i.e., after c. 520 BC), based on preexisting written and oral traditions, as well as contemporary geographical and political realities.^[9][10][2] The five books are often described as being drawn from four "sources", generally regarded as the works of schools of writers rather than individuals: the Yahwist and the Elohist (frequently treated as a single source), the Priestly source, and the Deuteronomist.^[11] There is an ongoing dispute over the origins of the non-Priestly source(s), but it is generally agreed that the Priestly source is post-exilic.^[12] Below is an outline of the hypothesis:

• Genesis is made up of Priestly and non-Priestly material.^[12]
• Exodus is an anthology drawn from nearly all periods of Israel's history.^[13]
• Leviticus is entirely Priestly and dates from the exilic/post-exilic period.^[14]
• Numbers is a Priestly redaction (i.e., editing) of a non-Priestly original.^[2]
• Deuteronomy, now the last book of the Torah, began as the set of religious laws that make up the bulk of the book, was extended in the early part of the 6th century BC to serve as the introduction to the Deuteronomistic history (the books from Joshua to Kings), and later still was detached from that history, extended and edited again, and attached to the Torah.^[15]

However, the Ketef Hinnom scrolls do point to the plausibility of a pre-exilic written tradition of the passage from Numbers 6 and Deuteronomy 7.^[3] Although this does not decisively prove that there was a canonical written tradition it does point to a possibility of such a tradition.

David A. Clines, in his influential The Themes of the Pentateuch (1978), identified the overarching theme of the five books as the partial fulfilment of a promise made by God to the patriarchs, Abraham, Isaac and Jacob. The promise has three elements: posterity (i.e., descendants—Abraham is told that his descendants will be as innumerable as the stars), divine-human relationship (Israel is to be God's chosen people), and land (the land of Canaan, cursed by Noah immediately after the Deluge).^[16]

The theme of the divine-human relationship is expressed, or managed, through a series of covenants (meaning treaties, legally binding agreements) stretching from Genesis to Deuteronomy and beyond. The first is the covenant between God and Noah immediately after the Deluge in which God agrees never again to destroy the Earth with water. The next is between God and Abraham, and the third between God and all Israel at Mount Sinai. In this third covenant, unlike the first two, God hands down an elaborate set of laws (scattered through Exodus, Leviticus, and Numbers), which the Israelites are to observe; they are also to remain faithful to Yahweh, the god of Israel, meaning, among other things, that they must put their trust in his help.^[17]

It is important to note that among the reasons this law was given was to establish the Israelite people as Yahweh's people. The laws and instructions were as much for identity as they were for obedience. Yahweh by providing all the different instructions and laws was affirming that the Israelite people were his and would bear his identity.^[18]: 246

The theme of descendants marks the first event in Numbers, the census of Israel's fighting men: the huge number which results (over 600,000) demonstrates the fulfillment of God's promise to Abraham of innumerable descendants, as well as serving as God's guarantee of victory in Canaan.^[19] As chapters 1–10 progress, the theme of God's presence with Israel comes to the fore: these chapters describe how Israel is to be organized around the Sanctuary, God's dwelling-place in their midst, under the charge of the Levites and priests, in preparation for the conquest of the land.^[20]

The Israelites then set out to conquer the land, but almost immediately they refuse to enter it, and Yahweh condemns the whole generation who left Egypt to die in the wilderness. The message is clear: failure was not due to any fault in the preparation, because Yahweh had foreseen everything, but due to Israel's sin of unfaithfulness. In the final section, the Israelites of the new generation follow Yahweh's instructions as given through Moses and are successful in all they attempt.^[20] The last five chapters are exclusively concerned with land: instructions for the extermination of the Canaanites, the demarcation of the boundaries of the land, how the land is to be divided, holy cities for the Levites and "cities of refuge", the problem of pollution of the land by blood, and regulations for inheritance when a male heir is lacking.^[21]

A large part of the theological theme in Numbers is the righteousness and holiness of God being met with human rebellion. The two censuses not only show the different response of two generations but rather that God had remained faithful despite the rebellion of the Israelites. The theme of the book should seem to be more centrally focused on the faithfulness and holiness of God as this is a common theme that runs through the whole of the Pentateuch, not just the book of Numbers.^[18]: 247

The book of Numbers records in some detail the population of the fighting men in Israel, providing a figure of approximately 600,000 soldiers. This would translate to a total population of 1.5 to 2.5 million Israelites. However, scholars have proposed multiple alternatives, as such a large number of Israelites does not conform to modern historical knowledge of the period or archaeological evidence. Some scholars see the book of Numbers as unhistorical, and the figures given as either greatly exaggerated or simply fabricated, opting instead to focus on Numbers as a theological book and not a historical one.^[22][23]

On the other hand, some Biblical scholars speculate that the literature is not referring to the actual number, and that the word for "thousand" is actually referring to a noun signifying a group or clan. However, this interpretation poses a problem, as it undermines the validity of the text, "assumes a misunderstanding and mistransmission of the text in all the census lists of Exodus and Numbers (not to mention other texts)"^[24] and produces several inconsistencies in the book of Numbers that cannot be resolved. Most scholars who hold this view posit a much lower number for the fighting men of Israel, closer to 20,000.^[25] Another theory is that of an error in transmission, with J.W. Wenham arguing that "biblical texts are often corrupted by the simple addition of zeroes to the numbers",^[24] although the flaw in this suggestion "is that the mistake in zeroes would easily occur only where numbers were represented by figures rather than by words",^[24] and there is "little or no evidence that figures were used in the biblical texts during the biblical period."^[24] Based on the nature of the book and the many accounts of tax payment and records of animals and persons, it is most likely that Numbers is referring to an actual account of a numerical tally of the Israelite people. A more likely explanation for the large number stated in the book is that the actual numerical metrics cannot really be established today. This requires us to take the values given as they are, as any other alternatives raises more problems than solutions.^[18]: 246 In his commentary on the book of Numbers, John Calvin acknowledged that even among his contemporaries, "certain sceptics"^[26] had questioned the veracity of the figures quoted, but defended the inerrancy of the text by invoking the miraculous "interference of God".^[26]

According to Timothy R. Ashley's analysis:^[24]

No one system answers all the questions or solves all the problems. [...] In short, we lack the materials in the text to solve this problem. When all is said and done, one must admit that the answer is elusive. Perhaps it is best to take these numbers as R.K. Harrison has done—as based on a system familiar to the ancients but unknown to moderns. According to Harrison the figures are to be taken as "symbols of relative power, triumph, importance, and the like and are not meant to be understood either strictly literally or as extant in a corrupt textual form."

• Bemidbar, on Numbers 1–4: First census, priestly duties
• Naso, on Numbers 4–7: Priestly duties, the camp, unfaithfulness, and the Nazirite, Tabernacle consecration
• Behaalotecha, on Numbers 8–12: Levites, journeying by cloud and fire, complaints, questioning of Moses
• Shlach, on Numbers 13–15: Mixed report of the scouts and Israel's response, libations, bread, idol worship, fringes
• Korach, on Numbers 16–18: Korah's rebellion, plague, Aaron's staff buds, duties of the Levites
• Chukat, on Numbers 19–21: Red heifer, water from a rock, Miriam's and Aaron's deaths, victories, serpents
• Balak, on Numbers 22–25: Balaam's donkey and blessing
• Pinechas, on Numbers 25–29: Phinehas, second census, inheritance, Moses' successor, offerings and holidays
• Matot, on Numbers 30–32: Vows, Midian, dividing booty, land for Reuben, Gad, and half of Manasseh
• Masei, on Numbers 33–36: Stations of the Israelites' journeys, instructions for conquest, cities for Levites

• Balaam
• Book of the Wars of the Lord
• Inverted nun (only appears twice in the Book of Numbers and seven times in the Book of Psalms)
• Ketef Hinnom scrolls
• Ordeal of bitter water
• Priestly Blessing
• Torah
• What hath God wrought (disambiguation)
• Wilderness of Sin