The parsha of Beha`alotekha begins with details about the special duties of the tribe of Levi (Numbers 8). A little later, it describes how the tribes marched in formation (10:11–28). Then, there is the conversation between Moses and Chovev (a.k.a. Jethro), where the latter, despite Moses’ urgings, decides to go home to his own family. A few verses after that, we have the episode with the quail, which begins as follows: “The afsafsuf in their midst had a great craving, and even the Israelites sat and cried, ‘Who will give us meat?’” (11:4).
The commentators agree that the afsafsuf here is the `erev rav, the “mixed multitude,” that left Egypt alongside the descendants of Jacob (Exodus 12:38). What do these people have in common with Jethro? They did not belong to any tribe, and the pageant described in the preceding chapters does not define any role for them.
It can’t be a coincidence that the `erev rav started causing trouble so soon after the most prominent local convert took his leave, can it? My wife suggests two possible reasons: