מָגֵ֨ן גִּבֹּרֵ֜יהוּ מְאָדָּ֗ם אַנְשֵׁי־חַ֙יִל֙ מְתֻלָּעִ֔ים בְּאֵשׁ־פְּלָד֥וֹת הָרֶ֖כֶב בְּי֣וֹם הֲכִינ֑וֹ וְהַבְּרֹשִׁ֖ים הָרְעָֽלוּ׃
Щит его могущественных людей сделан красным, доблестные люди в алом; Колесницы - стальной огонь в день его приготовления, и кипарис копья сделаны, чтобы дрожать.
Rashi
a cup of weakness a vessel of weakness, as in (Exod. 12:22), “in the blood that is in the cup.” weakness an expression of bewilderment, [it means] the clogging of the heart and the limbs, for, like man enwrapped in a garment, they have no strength, as in (Nahum 2:4), “And the cypress trees were enwrapped” ; and (Isa. 3:19) “And the bracelets and the veils.” In the language of the Mishnah (Shabbath 6:6) we find, “Arabian women may go out veiled.” It is involopiment in O.F.
Abarbanel
And because of this, He will make Jerusalem a "cup of poison" for all the nations — meaning, a cup of deadly poison, so that whoever drinks from it will die. So too, all those who besiege Jerusalem will be annihilated and perish without any effort. There are those who interpret "cup of poison" as connected to the word "end" (סוף) and "poison" (רעל) as meaning desolation, as in "and the cypresses languish" (Nahum 2:4). According to this, it means that Jerusalem will, at that time, be the end of destruction and desolation for all the nations. As for the phrase "and also upon Judah will be the siege," the commentators explained that Judah, too, will experience the cup of poison, since they will come along with the nations to besiege Jerusalem. Therefore, they too will suffer many troubles and calamities. However, it is more correct to explain that the "cup of poison" mentioned will also affect Judah, and the bet (ב) in "במצור" (in the siege) is a bet of causality — meaning "because of the siege" that will come upon Jerusalem, and because the people of Judah will be there, the cup will also pass over them. And with this, the first question is resolved.
Rashbam
ותולעת שני, wool dyed red is called תולעת. The colour itself is called שני. We know this from Nachum 2,4 אנשי חיל מתולעים, “soldiers dressed in crimson.” The word also occurs in that sense in Lamentations 4,5 האמונים עלי תולע, “the ones who used to be robed in purple, etc.” The prophet Isaiah 1,18 holds out the hope that “if our sins were staining our clothing red, repentance would result in their becoming white as snow.” The prophet considers both the word שלג and שני as dyes, the former being a white dye, the latter a red dye. However the words תולע and צמר both refer to wool, the latter being undyed wool.
Rashi
wine of bewilderment Heb. תרעלה. [Wine] that stops up the heart and envelops it. רַעַל is an expression of envelopment, as (Nahum 2:4): “and the cypresses are enwrapped (הרעלו),” and the language of the Mishnah (Shab. 6:6): “Median women shawled (רעולות).”
Rashi
weakness Heb. תַּרְעֵלָה. That is a drink that clogs and weakens the strength of a person, like one bound, tied, and enwrapped. Comp. (Nahum 2:4) “And the cypress trees were enwrapped (הָרְעָלוּ).” Also (supra 3: 19), “And the bracelets and the veils (רְעָלוֹת),” which is an expression of enwrapping, and in Tractate Shabbath (6:6): “Median women (sic) may go out veiled (רְעוּלוֹת),” a kind of beautiful veil in which to enwrap oneself.