The book of Vayikra ends with the end of Parashat Bechukotai, and it is followed with Bamidbar (the book and the parasha). The two books have very different styles, and their differences are reflected in the transition between the two.
The expected end of the book of of Vayikra would have been one chapter earlier, with this concluding verse:
“These are the laws, rules, and instructions that the LORD established, through Moses on Mount Sinai, between Himself and the Israelite people.” (Vayikra 26:46)
But then there is an additional chapter (27), which provides the laws of funding the mishkan, via various types of voluntary contributions. Why was this epilogue added?
Rabbi Amnon Bazak offers an interesting explanation. He suggests that this appendix is different from all the laws that preceded it in Vayikra. Earlier we read about sacrifices that people were commanded to bring. And even the voluntary sacrifices had a benefit to those who brought them – atonement for their sins, or to those who were allowed to consume them. But with the donations in chapter 27, no benefit is mentioned at all – it was for the “sake of heaven”, motivated only by a desire to give. For this reason it follows the section of the blessings and the curses – since no blessing was expected for these acts.
I think that this chapter can therefore be understood as a “sneak preview” for the upcoming book, Bamidbar. As Netziv writes in his introduction to his commentary on Bamidbar, this fourth book of the Torah represents the transition from reliance on God’s miracles, as seen in the earlier books, to a natural state, where people are responsible for their successes and failures. The book of Bamidbar contains many failures – from the sin of the Spies, to the rebellion of Korach, but also unprecedented successes, like the war against the king of Arad (Bamidbar 21:1), where the people, on their own, vow to fight and redeem the captives.
That volunteer spirit, accompanied with sacred vows, begins in the last chapter of Vayikra.
Another example of that transition is found in the beginning of Bamidbar. The parasha opens with the command to take a census. The last time we read about a census was in Ki Tisa (Shemot 30:11-16). The results of the census are found in Parashat Pekudei, where it says that 603,550 men were counted. Remarkably, the census in Parashat Bamidbar has the same number of people counted (Bamidbar 1:46). The commentators struggle with this, since the two censuses would appear to have occurred about six months from each other – what are the odds that the population would be exactly the same? And why would there be a need for a second census so soon after the first one?
Cassuto in his commentary, and expanded upon by R. Elchanan Samet, explains that this was the same census. The process began as recorded in Ki Tisa, and the final results were announced in Bamidbar.
However, even if it was one census, they are described as having very different goals. The census in Ki Tisa fits the theme of that parasha and the ones following it – the money was collected to fund the mishkan. But in Bamidbar, the purpose of the census appears to be preparation for the continuation of the journey of the people and the eventual conquest of the Land of Canaan. The people being counted are the focus, and it will be up to them to make the right decisions for a successful future.