When will Bnei Yehudah and Bnei Yisrael gather together?
Radak: This will be when the exiles are gathered in Yemos ha'Mashi'ach. In Bayis Sheni, only Yehudah and Binyamin, who were exiled to Bavel, ascended. Bnei Yehudah and Bnei Yisrael were not together.
Malbim: It will be in the end of days. Both Bnei Yehudah, whom Nebuchadnetzar exiled in Churban Bayis Rishon (not all of them returned in the days of Ezra), and Bnei Yisrael (the 10 tribes, whom Melech Ashur exiled) will gather from where they are scattered.
Who will be "Rosh Echad"?
Rashi: David, their king.
Radak: It is Melech ha'Mashi'ach.
Radak citing Targum Yonasan: They will appoint one head from Beis David.
Malbim: Initially, Mashi'ach ben Yosef will head them, like I explained in Yechezkel (refer to Yechezkel 37:19:3:3).
Will they ascend after appointing a head?
Radak #1: No. The prefix Vov in "v'Alu" means after they ascended, like the Vov in "Atah Katzafta v'Necheta" (Yeshayah 64:3 after we sinned, You became angry), "va'Yered me'Asos ha'Chatas veha'Olah" (Vayikra 9:22), "va'Yaram Tola'im va'Yiv'ash" (Shemos 16:20) and similar verses. Mashi'ach will be the head only after they will be in Yerushalayim.
Radak #2: Yes ? Eliyahu ha'Navi will raise them from Galus.
From which land will they ascend?
Radak: From the land of their Galus they will ascend to their land.
Radak citing some Meforshim: They will go [from Eretz Yisrael] to Galus 1 .
Malbim: From the entire earth, where they were dispersed.
Radak: This is wrong. How does one head apply to Galus? (There was a Reish Galusa! ? PF) Also, it should say 'v'Yardu', for Eretz Yisrael is higher than all other lands; one who leaves it, he descends.
What is "Yom Yizre'el"?
Rashi: The day when they will be gathered from where they were seeded.
Radak: It is the day when their bow was broken in Emek Yizre'el.
Malbim: Hoshe'a's first son was named Yizre'el, to show that Hashem's judgment was fulfilled on them in another way ? "u'Zratiha Li ba'Aretz" (25); Yizre'el refers to Zeri'ah (seeding). Galus will be like seeding seeds of grain deep in the ground. It seems that the seeds rotted; later, they sprout and yield far more than their quantity. So will sprout from the exiles seeded in other lands, a nation that cannot be counted, like sand, with converts accompanying them, like Chazal said. Yom Yizre'el is the day when the fruits of the seeding will be revealed.
What is great about "Yom Yizre'el"?
Radak: Their Galus was very long. [Punishment for] their sin was finished in the long Galus.
Radak citing his father: They were Zeru'im (seeded) in Galus for a long time, and now I will gather them. Yisrael are called Yizre'el, for Hashem was Zore'a them amidst the Goyim.
Malbim: Hashem will do great miracles on that day in the eyes of all Goyim.
