1)
The previous verse said "va'Ya'amidu". Why is this repeated?
1.
Rashi: They stood to sing together around those who made the foundation.
2.
Malbim: Before they stood to sing. Now they stood to oversee the work.
2)
Why does it say "Yeshu'a Banav"?
1.
Ibn Ezra: It means Yeshu'a u'Vanav (the prefix Vov is omitted). Similarly, "Bnei ha'Nedad" (later in this verse) is like u'Vnei ha'Nedad.
3)
Why does it say "Bnei Yehudah"?
1.
Malbim: This teaches that these Bnei Kadmi'el are not the Leviyim mentioned in Nechemyah 10:10.
