What is the meaning of "ha'Ba'im Yashresh Yakov"?
Rashi: They are those who came to Egypt, that Yakov rooted there.
Radak: The days to come, of salvation. This is like "Hinei Yamim Ba'im Ne'um Hashem va'Hakimosi l'David Tzemach Tzadik" (Yirmeyah 23:5). In those days, Yakov will put a root, like "va'Yach Sharashav ka'Levanon" (Hoshe'a 14:6). Now, in Galus, [Am Yisrael] is like one who has no root. Then, it will sprout above.
Malbim: Now it explains who is the vineyard of good wine discussed until now. It comes from the root of Yakov.
What is the meaning of "Yatzitz u'Farach Yisrael u'Mal'u Pnei Sevel Tenuvah"?
Rashi: They sprouted there, until they filled [all] the settled land [like] vegetation. Radak - it is as if it says ki'Senuvah; the prefix Kaf is omitted, like "Lev Soma'ech Yeitiv Gehah" (Mishlei 17:22) means k'Gehah.
Malbim: The verse compares Yisrael after Galus, and all the killing done to them, to a vineyard that was totally destroyed, and only the root remains. It will sprout and multiply so much that all the settled land will be filled; it will be a great vineyard over which this song will be sung.
