Can a few verses really be what holds the world up?
The Mishnah (the Sages' teachings written down around 200 CE) says that since the Temple was destroyed, every day has a curse in it. Rava (a leading sage of the Gemara) adds that each day is more cursed than the one before. So how does the world survive? The Gemara answers: by the Kedushah DeSidra (this section), and by "Let His great name be blessed" after a Torah talk. Its proof is a verse from Iyov (the book of Job) about a dark land with "no orders": where there are orders, light breaks through.
The Gemara does not say how this works. Rashi (the main commentator on the Gemara, who died in 1105) gives a reason. This section was set up so that every Jew, scholar or not, gets a small piece of Torah each day: a verse and its translation, which counts as learning. It holds two precious things at once: making God's name holy, and learning Torah.
Abudarham (a commentary on the prayers from Spain, 1300s) gives a different reason for the placement. It was set up for people who came late to the synagogue and would otherwise miss the Kedushah. That is also why it was translated: ordinary people spoke Aramaic and did not know Hebrew well.
The Arukh HaShulchan (a law code from around 1900) asks your question: how does this cancel a curse? His answer starts from a midrash (a teaching of the Sages on a verse) about Tehillim 20: in trouble, what helps most is to make God a partner in our pain. These verses do that. They say the whole earth is full of God's glory, though right now it cannot be seen at all, and they ask when His kingship will show. Then, he says, God, as it were, cries out with us and lifts the curse.
Rashi's reason and Abudarham's are both about people: a daily share of Torah for everyone, and no one missing the Kedushah by coming late. That the world stands on it is the Gemara's claim. How it works, each commentator explains his own way.
Sotah 49a,Rashi on Sotah 49a,Abudarham, Weekday Prayers, Post Amidah 22,Arukh HaShulchan, Orach Chaim 132:5What redeemer is this waiting for, and what does it have to do with me?
The prayer opens with a verse from the prophet Yeshayahu: "A redeemer will come to Zion, and to those in Jacob who turn back from rebellion." Ibn Ezra (a Bible commentator from Spain) says the redeemer in the verse is the Messiah.
The verse has two halves, and the Gemara pays attention to how they connect. Rabbi Yonatan (a sage of the Gemara) teaches that teshuvah, turning back, brings the redemption closer. Then he asks why the verse says a redeemer will come to Zion, and answers: because there are people in Jacob who turn back from rebellion. He reads the second half as the reason for the first.
So the opening line is not only a hope. In his reading, people turning back is the reason the redeemer comes.
The Arukh HaShulchan points to a pattern. In Yeshayahu, the redeemer verse comes right after a verse about trouble arriving "like a flood." In the siddur it comes right after Tehillim 20, which begins "May Hashem answer you on a day of trouble." The next verse in the prayer is the promise that God's words will stay in your mouth and in your children's mouths, and he reads it as a reassurance: do not fear that Torah will be forgotten because of so many troubles.
Rashi reads that second verse the same way: even in exile, God's Torah will not be forgotten by them.
The sources do not settle what the redemption will look like. What they do is tie it to people returning, and tie the promise of Torah to the people who come after you.
Yeshayahu 59:19-21,Yoma 86b,Ibn Ezra on Yeshayahu 59:20,Rashi on Yeshayahu 59:21,Arukh HaShulchan, Orach Chaim 132:4If the angels' words were already said in Hebrew, why say them again in Aramaic?
The sources give a plain reason first. The Rambam (Maimonides, who died in 1204) lists the order: the Hebrew verse, then its translation, "so the people understand." The Tur says the same: translate so that everyone understands. Aramaic was the language people spoke every day. The Kaddish DeRabbanan prayer goes further into why Aramaic is in the siddur at all.
But this is not just a word-for-word swap. These are the old Aramaic translations of the Bible, and they explain as they translate. You met one of them in Titbarach, before the Shema: in Yeshayahu the angels say "holy" three times, and the translation reads that as three places and times, the highest heavens, the earth, and forever. The Hebrew words alone do not say that. It is one old way of understanding them. Here you say that translation out loud.
In Yechezkel, the Hebrew has "the sound of a great rumble," and then "Blessed is the glory of Hashem from His place." The Aramaic says the rumble was made by those who were praising and saying it, and that the place is where God's presence lives.
Rashi gives a second reason. Reading the verse and its translation counts as learning Torah, so everyone gets a bit of study every day. The same pairing of text and translation shows up in a rule in the Gemara: keep up with the weekly Torah portion along with the community, reading it "twice in the Hebrew and once in the translation."
The Rambam and the Tur both say the translation is there so the listener understands, not only so the words get said. Rashi adds that saying it this way counts as learning Torah.
Rambam, Laws of Prayer and the Priestly Blessing 9:5,Tur, Orach Chaim 132,Targum Yonatan on Yeshayahu 6:3 and Yechezkel 3:12,Rashi on Sotah 49a,Berakhot 8a