Numbers 16 - This chapter presents what is known as "Korah's Rebellion." Seems the Levitical family of Korah with Dathan and Abiram leading the way, didn't learn from Aaron and Miriam's mini-revolt against Moses back in chapter 12. God had made it clear then that He had chosen Moses as His spokesman. Now Dathan and Abiram were leading a rebellion of their own emphasizing the fact that Israel was not in the land of "milk and honey." Of course, they seemed to easily overlook why they were still in the wilderness: they disobeyed God and wouldn't trust Him. The startling way God judged this family was a very clear demonstration of God meaning business! Even after the rebellion the children of Israel continued to complain!
Numbers 17 - How does God make things clear? Use an object lesson. So, He ordered the leader of every tribe to present a rod to Aaron and he would put them in the Tabernacle overnight. The rod that budded and had edible almonds on it would be the rod of the tribe of people God chose. And that tribe was clearly the Levites. This chapter closes with a mournful cry from the people that revealed how hard their hearts were.