What rock did He put in front of Yehoshua?
Rashi: It is the foundation of the Bayis that you made in the days of Koresh, and it was ceased. That Yesod and the thickness of the wall was small in your eyes, like it says in Ezra (3:12) and Chagai (2:3).
Radak #1: It is Even ha'Bedil (tin) used to straighten the building.
Radak #2: The rock that they will put first, like it says below that Zerubavel will put it in front of Yehoshua ? "v'Hotzi Es ha'Even ha'Roshah" (4:7). Malbim ? this was the cornerstone. It was proper that the Kohen set it down. It is Midas ha'Malchus ? "Even Ma'asu ha'Bonim" (Tehilim 118:22).
Why does it say that there are seven eyes on one rock?
Rashi #1: In the end it will be widened seven-fold. Targum Yonasan is like this. "Einayim" it is an expression of visions.
Rashi #2: This refers to Hashem's eyes. It is in His eyes and heart to increase seven-fold. We find like this ? "v'Ra'u Es Even ha'Bedil b'Yad Zerubavel Shiv'ah Eleh Einei Hashem Hemah Meshotetim b'Chol ha'Aretz" (4:10). Why does it say here that seven eyes of Hashem roam? Rather, this teaches that He put His eyes to increase the honor of the building of the Bayis.
Radak: Hashem will guard every rock greatly, due to the afflicters who intended to cease the work. These are the seven eyes mentioned below (4:10). Seven is the number used to signify many. It is not precise, e.g. "Sheva k'Chatoseichem 1 ", "Sheva Yipol Tzadik v'Kam" (Mishlei 24:16) and similar verses.
Radak citing his father: There are precisely seven ? Yehoshua, Ezra, Zerubavel, Nechemyah and three Nevi'im ? Chagai, Zecharyah and Malachi.
Radak citing Targum Yonasan: Seven eyes see it.
Malbim: Yehoshua carved into the rock the form of seven eyes, to hint that Hashem's seven eyes roam over the land ? the influence of the seven Kochvei Leket (the sun, moon and five closest planets). Hashem conducts natural conduct via them, arranged from the six days of creation. They are engraved on the cornerstone of the Mikdash, for from now Hashgachas Hashem will be via the Mikdash, in which He will dwell, and from there He will supervise His world. These seven eyes supervise via the seven Kochvei Leket; they draw influence from the seven supreme eyes above them, until the seven Sefiros of the building. Influence descends from them to the seven lower eyes. Man carved the seven eyes on the rock ? man's deed will last. Nowadays, the lower eyes (the Ma'arachah and stars) rule.
Vayikra 26:21. Rashi there struggles to explain that it is precise. (PF)
What will He untie?
Rashi: I will untie its binds. I will annul the enemy's counsel ? they wrote prosecution to cease the work (building).
Radak #1: It is as if the rock was tied all the days that the work was ceased. Now He will open it and put it in the building.
Radak #2: This is like "u'Fitachta Alav Pituchei Chosam" (Shemos 28:36). The completion of a nice rock is designs, flowers and buttons that they engrave on it. This is a Mashal ? I will complete the building in all aspects.
Malbim: When I will bring Avdi Tzemach, I will open this lock and image of eyes, like the next vision explains.
What is the meaning of "u'Mashti"?
Rashi: I will remove. Radak ? this is Po'el Yotzei (it acts on others); Mashu is Po'el Omed (the action applies only to the subject). This will be at the time that the Nevi'im promised that Zerubavel's level will be raised - "Ekachacha Zerubavel?" (Chagai 2:23), "Hineni Mevi Es Avdi Tzemach" (the previous verse). Then Yisrael will be in serenity in Bayis Sheni, therefore it says "Tikre'u Ish El Re'ehu" (the coming verse).
What is "Avon ha'Aretz"?
Radak #1: This is like the simple meaning (the sin of the land). Malbim ? then, people will not sin, and I will pardon what they already sinned.
Radak #2: It is the punishment [of the land], like "Ki Lo Shalem Avon ha'Emori" (Bereishis 15:16). I.e. at that time He will remove from them all evil and affliction, and they will live in Shalom.
Which day is this?
Rashi: I do not know.
Additional comment in Rashi: It is the day that they began to add to the building. He will remove the land's sin, and there will be Brachah in Peros of the land. Now there is a curse, like it says in Chagai 2:18-19.