Why does it say "ha'Adon"?
Radak: This informs them that He is the Master. He can destroy, build, satiate or make hungry. They do not consider Him to be the Master, and they turn to their deeds. If they considered Him to be the Master, they would not sin, and would not depart from His Reshus and command!
Do we find that Hashem removed food and water from Yerushalayim?
Rashi (from Chagigah 14a): Yeshayah cursed Yisrael with 18 curses. He was not assuaged until he said "Yirhavu ha'Na'ar ba'Zaken veha'Niklah ba'Nichbad" (5).
Is there a reason why this follows the above Parashah?
Rashi: Yes. Above it discusses the eradication of Resha'im in the days of Mashi'ach. Now it discusses judgment of Resha'im in Yerushalayim and Yehudah. The adults will perish via hunger and the sword, and the youths will remain.
Why does it say "Mash'en u'Mash'enah"?
Radak: The matter is doubled to strengthen it, like is common. It uses different words - masculine and feminine. It says Mash'en, for food and drink are the body's supports; via them, it lives. The Torah says "b'Shivri Lachem Mateh Lechem" (Vayikra 26:26) - like a Mateh (staff) that a person leans on, so is food and drink.
Radak (3, citing Chagigah 14a): Mash'en knows Talmud - "Lechu Lachamu v'Lachami u'Shesu b'Yayin Masachti" (Mishlei 9:5). Mash'enah knows Agadah; he draws a person's heart with Agadah.
Malbim: Mash'en is [a] big [support], and Mash'enah is small. Success of the nation depends on seven matters (that the verses list); there will not be even a small support for any of them. (a) Rich, generous people who support the weak. Food is a big support; water, which is cheap, is a small support. Also refer to 3:2:2:2, 3:2:3:2, 3:3:2:3. 3:3:3:4, 3:3:5:4.
