Who are "Tzorefim"?
Rashi: That family was called so based on their trade (smelters).
What do we learn from "va'Ya'azvu Es Yerushalayim"?
Rashi: They filled it with earth until the wide wall, to strengthen it.
Ibn Ezra: This is like Chachamim say, Ma'azivah (a plastered roof).
Ibn Ezra: Some say that it is [helping,] like "Azov Ta'azov Imo."
Malbim: They strengthened and fortified it. Mountains do not surround Yerushalayim in the north, rather, a plain, so that wall needed to shield against enemies.
Between the wide wall and Sha'ar ha'Yeshanah there was Sha'ar Efrayim (12:38-39). Why is it not mentioned here?
Malbim: Yo'ash breached from Sha'ar Efrayim until Sha'ar ha'Pinah, 400 Amos (Divrei ha'Yamim II, Perek 25). Sha'ar ha'Pinah was Sha'ar ha'Yeshanah, in the northeast corner. We must say that Sha'ar Efrayim was not destroyed so much, so the verses do not mention rebuilding it; it is among the Klal of the wall.
