What is written on the first stick?
Rashi: "Li'Yhudah veli'Vnei Yisrael Chaverav."
Who are "Bnei Yisrael Chaverav"?
Rashi: It is Shevet Binyamin which accompanied (was together with) Yehudah [Radak ? even after the kingdom was divided].
Shimon's inheritance was amidst Yehudah! Why is it counted among the 10 tribes? Perhaps most lived among the other Shevatim; refer to Melachim I, 11:31:1:1-3 and the notes there. (PF)
After Pilegesh b'Giv'ah, only 600 men remained in Shevet Binyamin. They could not farm an inheritance proper for 45,600; presumably, many came from other tribes to live in Binyamin. Also, this can explain Binyamin's population explosion ? they had more than 280,000 men in the days of Asa. According to the opinion that Pilegesh b'Giv'ah occurred at the end of the Shoftim (where it is written), this was at most 146 years later ? refer to Shoftim 17:1:1:2*). (PF) Afterwards, many from Malchus Yisrael came to Yehudah and Binyamin upon seeing Asa's success (Divrei ha'Yamim II, 15:9).
What is written on the second stick?
Malbim: "L'Yosef Etz Efrayim v'Chol Beis Yisrael Chaverav." This is a sign for Yosef, who was the head of the Shevet, and from him sprouted Malchus Efrayim.
Why are the other Shevatim called on the name of Efrayim?
Radak: When the kingdom split, Melech Yaravam was from Shevet Efrayim.
Who are "v'Chol Beis Yisrael Chaverav"?
Rashi: It is the other nine Shevatim which followed Yaravam, who was from Shevet Efrayim.
Why is "Chaverav" written without a Yud both times in this verse?
Radak: The first time, the Kesiv is singular to hint that it was only one other Shevet (Binyamin). The second time, it refers to the Klal, like it says "Beis Yakov."
