The Temple fell "because of our sins." I was not there. Why "our"?
The prayer could have said "their sins." It says "our sins." Musaf, the additional prayer of the festivals, does the same: "Because of our sins we were exiled from our land." The Second Temple fell more than 1,900 years ago. So what does "our" mean?
Start with what the sins were. The Gemara (the rabbis' discussions built on the Mishnah) says the First Temple was destroyed for three things: idol worship, forbidden sexual relations and bloodshed. The Second Temple is the surprise. The Gemara says the people of that time were busy with Torah, mitzvot and acts of kindness. It fell because there was hatred for no reason. The Gemara's lesson: hatred for no reason weighs as much as the other three together.
The Talmud Yerushalmi (the Gemara of the Land of Israel) tells it almost the same way, and adds that they loved money. Then it gives a line that speaks to this question: "Every generation in whose days it is not rebuilt is counted as if it destroyed it."
The Yerushalmi does not say why. The Yalkut Shimoni (a medieval collection of midrash) quotes the line and adds a reason: "because it did not repent."
So "our" is not a claim that you were there. One way to read these sources: what brought the Temple down has not yet been repaired, and the repair is the job of every generation, including this one. That is a heavy thing to say each morning, and the sources do not soften it. The sin they name for the Second Temple is about how people treat each other.
Yoma 9b,Talmud Yerushalmi, Yoma 1:1,Yalkut Shimoni on Tehillim, section 886,Siddur Sefard, Musaf for the festivalsIs saying the words as good as the real offering, or is it second best?
The Kiyor passage, earlier in the siddur, already asks why we read about offerings at all. This is a different question. Does the reading fully count, or is it a stand-in until the real thing comes back?
The prayer itself sounds like loss. It lists what is gone: no kohen (priest) at his service, no Levite on his platform, no Israelite at his post. And it asks only that our words count "as if" we had brought the offering.
Now listen to Rabbi Elazar in the Gemara: "Prayer is greater than offerings." A few lines later the same Rabbi Elazar says: "From the day the Temple was destroyed, the gates of prayer have been locked." The gates of tears, he adds, were not locked. Both statements are his, on the same page.
The verse that closes this prayer begins: "This is the teaching of the burnt offering, the grain offering, the sin offering and the guilt offering." The Gemara gives those words two readings. Reish Lakish: whoever is busy with Torah is counted as if he brought all four. Rava goes further: whoever is busy with Torah does not need them.
A midrash in Shemot Rabbah (a collection of rabbinic teachings on Shemot) pictures a conversation. Israel says: we are poor, and we have no offerings to bring. God answers: I am asking for words, meaning words of Torah. They say: we do not know any. God says: cry and pray before Me, and I will accept it.
On the other side, the Rambam (Maimonides, who died in 1204) writes in his code of law that the Mashiach (the Messiah) will rebuild the Temple, and offerings will be brought again. The request before the daily offering verses asks for the same thing.
So the sources hold both. Words count, maybe more than we assume. And something is missing that words do not replace. This prayer says both at once.
Berakhot 32b,Menachot 110a,Shemot Rabbah 38:4,Rambam, Laws of Kings 11:1A goat as a sin offering "to Hashem"? Since when does God need one?
Look at the last verse added on Rosh Chodesh (the first day of a Hebrew month): one goat "as a sin offering to Hashem." The festivals have a goat like it. Only here does the Torah add "to Hashem." The Gemara noticed.
It tells a story. The Torah calls the sun and the moon "the two great lights," and then, in the same verse, the great one and the small one. The moon said to God: can two kings share one crown? God said: go and make yourself smaller. The moon protested: I said something right, and I should shrink? God offered one comfort after another. The moon was not comforted. So God said: "Bring an atonement for Me, because I made the moon smaller." Reish Lakish says that is the goat of Rosh Chodesh.
Rashi (the classic Torah commentator, France, died 1105) gives a legal reading first. This goat atones for impurity brought into the Temple that no person ever found out about. Only God knows of that sin. Then he brings the moon story as a midrash.
Rabbeinu Bachya (Spain, about 1300) collects more. He quotes the Rif (Rabbi Yitzchak Alfasi, 1000s) that the Hebrew word for "for Me" is to be read like "to Me," and says most commentators read it that way. As he explains the story, God gave the moon the honor of this offering to make peace with her, to show that God does not want one of His creatures accusing another.
The Rambam, in the Guide for the Perplexed (his book of philosophy), reads the words with no story at all. The Egyptians of old brought offerings to the moon at each new moon. The Torah says "to Hashem" so that no one thinks this goat is for the moon.
Ibn Ezra (a Spanish-born Bible commentator of the 1100s) notes that the grammar points the opposite way from the midrash, and says only: "it has a secret." Rabbeinu Bachya also calls it one of the hidden matters of the Torah. The commentators do not settle on one meaning.
Bamidbar 28:15, with Rashi, Ibn Ezra and Rabbeinu Bachya,Chullin 60b,Bereishit 1:16,Rambam, Guide for the Perplexed 3:46 (Ibn Tibbon's Hebrew)