The four episodes (not Pinchas, which doesn't fit the pattern) of "unknown halakha" have striking literary parallels, a whole set of linguistic and thematic similarities. Some features are common to all; other features are found in subsets. To chart these patterns, I find it helpful to arrange them in a square:

A. Mekoshesh C. Mekalel
B. Pesach Sheni D. Benot Tzelafhad

Perhaps the most interesting pattern is the question of whether the plaintiff(s)/transgressor is named (i.e., has an identity beyond the particular action or plea) and has his or their voice heard in the text:

A. No voice and no identity C. Identity but no voice
B. Voice but no identity D. Both voice and identity

For rabbinic perspectives, see the following midrashic sources that link them in various ways:

Torat Cohanim on Vayikra 24: 12 (cf. Sanhedrin 78b)

Sifre 68, 114, 133 (cf. Bava Batra 119a)
Sifre 113 (cf. Shabbat 96b)
Targum Neofiti on Bemidbar 15: 34

Some readers may also be interested in a doctoral dissertation on exactly these four cases: Simeon Chavel, “Law and Narrative in Four Oracular Novellae in the Pentateuch: Lev 24:10–23; Num 9:1–14; 15:32–36; 27:1–11” (Ph.D. diss.; Hebrew University, 2006). Chavel, presently at Princeton, is preparing a book with Mohr Siebeck: Oracular Law and Narrative History in the Priestly Source.

Jon A. Levisohn
Brandeis University