Numbers 1:1 to 4:20, Hosea 2:1-22
The book Sh'mot (Exodus) ends with the tabernacle's completion on the 1st day of the 1st month of the second year (Exodus 40:17). Now it is one month later.
The census of chapters 1 and 2 is a preparation for war. Men who are not Levites must be 20 to be counted (verse 1:3). The census of chapters 3 and 4 is a preparation for tabernacle use. Levites need only be 1 month to be counted (verse 3:14).
God speaks only to Moshe. But Aharon and the clan chiefs are also involved in actually taking the census. They act the same day God spoke. God values both promptness and middle-management. (And conscription!)
Even though he had help, Moshe gets the credit (verse 1:19) Why? What kind of credit? What does this say about humility and authority?
Note that until the Last Days God has promised that Israel will be the "smallest of nations". The size of the nation does not increase during the 40 years in the wilderness.
Notice that in chapter 2 the nation of Israel is told to make camp in the shape of a cross. The tabernacle is in the center. The long foot of the cross is first and points east.
What did so many Levites do? It does not take six thousand men to maintain tent poles!
Hosea chapter 2 begins with a promise of Israel becoming uncountably numerous. The covenant is eternal and not dependent upon the Jewish people's faithfulness, just as Hosea loves his children even when he is not sure he is the biological father. But the Jews face consequences even if (and indeed because) the covenant is eternal.
The verb normally translated "take a census" literally means "lift a census" (1:2,49, 3:40, 4:2,22). Is there a connection between "lifting a census" and lifting (carrying) the Tabernacle's pieces in verses 1:50, 4:15, and 4:25?
Verse 1 emphasizes "in the wilderness". This is the Tenach's version of "dead to yourself". The desert is owned only by God and available to all, like a student of the Torah. "Anyone who does not make himself ownerless like the desert cannot acquire wisdom or Torah, and therefore it says, '...in the Sinai desert.'" (Bamidbar Rabbah 1:7) "Torah can only be preserved in one who kills himself for it." (Sotah 21a). Also Pirkei Avos 6:4.
Jeremiah 2:2 compares the Israelite's willingness to enter the wilderness with a bride's willingness to enter nuptuals.
In verse 2 the phrase "take a census" literally means "lift up the heads". Later the verse says the census is to be done "according to the number of the names". Each man's name was said or written, which gave encouragement.
The word vryityaldu (and they established) in verse 1:18 is literally the reflexive "and they gave birth to themselves". One interpretation, by Horav S.R. Hirsch, is that the command "be fruitful and multiply" is equivalent to "have children and raise them to duplicate your virtues". Hirsch conjectures that the Israelites, during the census, were not only counted but had to explain their Judaic virtues.
According to tradition the banners for each tribe were designed by God, and dwelling in the desert under such a symbol of intimacy is preferable to living in a palace distant from God. The multiple banners remind us that different people serve God in different ways. (Yalkut 684)
Chapter 3 says it will list the descendants of both Moshe and Aharon. But it only lists Aharon's. The traditional interpretation, by Rashi (and others), is that Moses taught Aharon's sons Torah and thus was viewed as their spiritual father.
Kehas was Levi's second son, but now has precedence because Moshe and Aharon were of Kehas.
The Or ha'Chayim comments that Numbers 1:3 claims every man over twenty years of age was fit to serve in the army. The miracle of God's protection of health (Deuteronomy 29:5) had already begun, and includes health.
HaRav Eliezer Chrysler expands on a phrase from verse 2:17: "as they encamped, so they traveled". The Israelites were not always on the march, but when they were resting they kept the same formation. Similarly, we cannot be constantly be doing good deeds—that is not our duty. But when we rest we should keep the same frame of mind and devotion to God as when we are doing good deeds.
The Ba'al ha'Turim notes the phrase be'mispar sheimos ("according to the number of names") is present in this Parasha but not the counting of Numbers 26. He explains that the phrase emphasizes that the Israelites retained records of their lineage during their time in Egypt; a fact not neccessary to repeat in chapter 26. Similary, the word b'nei (instead of li'vnei) appears only with the tribe of Naftali in this Parasha but with all the tribes in chapter 26: currently Naftali has more women than men, but after the men of the elder generation died all the tribes had more women than men.
The Ba'al ha'Turim says the word ve'choyu ("and they will live") appears only in Numbers 4:19 ("and they will live and not die") and Zechariah 10:9 ("and they will live with thier children and will return"), showing that in the days of the messiah people and their children will live forever.
Exodus 38:26 tells us that immediately after the episode of the golden calf there were 603,550 Israelite men over twenty years of age, including the Levites. Numbers 2:32 tells us that a month after the Tabernacle was set up there were 603,550 Israelite men over twenty years of age, excluding the Levites. The number of men who turned twenty during those months was equal to the previous number of adult Levites. The Or ha'Chayim taught that God purposefully waited until the numbers would match before asking for another counting.
The Tz'enah Ur'enah records that in verses 3:14-15 only Moshe is told to count the Levites, but verse 3:39 says that Moshe had Aharon help him with God's permission.