Why will Hashem send His angel?
Rashi: To eradicate the Resha'im.
Radak: If you want Mishpat of Resha'im in this world, the time will come when Mishpat will eradicate Resha'im amidst you. I will send an angel from Shamayim to clear the path. This is like "Hine Anochi Shole'ach Mal'ach Lefanecha Lishmarcha ba'Derech..." (Shemos 23:20).
How will the angel clear the path in front of Hashem?
Rashi: He will clear from it Resha'im.
Radak: This is the gathering of exiles. There will not be on their road any prosecution or mishap.
Malbim: Hashem will send a Navi to make the world repent.
What do we learn from "u'Fis'om Yavo El Heichalo"?
Radak: Because the Ketz (deadline for redemption) was not revealed in Sefer Daniel, it says that he will come suddenly. No one will know the day before he comes - "Ki Sesumim va'Chasumim ha'Devarim Ad Es Ketz" (Daniel 12:9).
Malbim: You want Elokei ha'Mishpat to appear suddenly and immediately punish the Resha'im and reward the Tzadikim. This cannot be in this world, for this is the world of choice. It must conduct according to nature, to leave room for tests, reward and punishment. If Hashem would appear in His honor, no one would do evil, for even for a small sin one would be punished immediately and pass from the world. Only after the world is fixed (repents), Hashem will come suddenly to dwell in His Heichal and go amidst you.
Who is "ha'Adon Asher Atem Mevakshim"?
Rashi: It is Elokei ha'Mishpat.
Radak: He is Melech ha'Mashi'ach, and "Mal'ach ha'Bris."
What is "Mal'ach ha'Bris"?
Rashi: He avenges the Bris.
Radak #1: Refer to 3:1:4:2.
Radak #2, Malbim #2: It is Eliyahu. A Midrash says that he had Kin'ah for Bris Milah, which Malchus Efrayim annulled - Kano Kineisi la'Shem Elokei Tzevakos Ki Azvu Brisecha Bnei Yisrael" (Melachim I, 19:10). Hashem said, you had Kin'ah in Shitim 1 , and here you have Kin'ah for Milah. Yisrael will not do Bris Milah until you see with your eyes! This is the source for the custom to make an honorable chair for Eliyahu, who is called Mal'ach ha'Bris.
Malbim #1: It is the angel that will enter the world in the Bris of Torah and Emunah, between them and Elokim.
This Midrash holds that Eliyahu is Pinchas. (PF)
What do we learn from "Hine Va"?
Radak: He will come in his time. The same applies to "Rishon l'Tziyon Hine Hinam" (Yeshayah 41:27).
