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וְהוּא רַחוּם

Vehu Rachum (part 1)

Part 1 of 4: verses of mercy, then a plea from Daniel. Mondays and Thursdays.

Daven with it Read it here

Draft. This siddur is waiting for a rav's review. For a halachic question, ask your rav.

At a glance

When: Said on Mondays and Thursdays, on days Tachanun is said.
Said: Standing up
Made of: Mostly verses from Tehillim, Yirmiyahu and Daniel
On other days: Skip ahead to Shomer Yisrael

The words

Hebrew, then English. Open "What it means" under any line for the explanation.

On Mondays and Thursdays say this. On other days with Tachanun, skip ahead to Shomer Yisrael:
וְהוּא רַחוּם יְכַפֵּר עָוֺן וְלֹא יַשְׁחִית וְהִרְבָּה לְהָשִׁיב אַפּוֹ וְלֹא יָעִיר כָּל חֲמָתוֹ.
And He, the merciful One, forgives wrongdoing and does not destroy and again and again turns back His anger and does not stir up all His rage
What it means
And He, the merciful One, forgives wrongdoing and does not destroy. Again and again He turns back His anger and does not stir up all His rage.
Rashi (the main medieval commentator, from France about 900 years ago) says that even when God punishes, He does not rouse all His anger, only a little at a time. Radak (a commentator from southern France about 800 years ago) says turning anger back takes strength of heart. The Romemu page tells where else this verse is used.
Rashi and Radak on Tehillim 78:38
אַתָּה יְיָ לֺא תִכְלָא רַחֲמֶיךָ מִמֶּנּוּ חַסְדְּךָ וַאֲמִתְּךָ תָּמִיד יִצְרוּנוּ.
You, Hashem, will not hold back Your mercy from us Your kindness and Your truth will always guard us
What it means
In Tehillim (the Book of Psalms) 40:12, David says "me" twice: "from me" and "will guard me." The siddur changes both to "us." Rashi explains the first verb as "withhold" and the second as "guard."
Tehillim 40:12; Rashi on Tehillim 40:12
הוֹשִׁיעֵנוּ יְיָ אֱלֺהֵינוּ וְקַבְּצֵנוּ מִן הַגּוֹיִם לְהוֹדוֹת לְשֵׁם קָדְשֶׁךָ לְהִשְׁתַּבֵּחַ בִּתְהִלָּתֶךָ.
Save us, Hashem our God, and gather us from the nations to give thanks to Your holy Name and to glory in Your praise
What it means
Save us, Hashem our God, and gather us from among the nations, to give thanks to Your holy Name and to glory in Your praise.
Radak says the one speaking here is people in exile: gather us, and then we will thank You. He says "Your praise" means the kindnesses God has done for us, which we praise Him for.
Radak on Tehillim 106:47
אִם עֲוֺנוֹת תִּשְׁמָר יָהּ אֲדֹנָי מִי יַעֲמֹד.
If You kept count of wrongdoings, Yah, my Master, who could stand?
What it means
Tehillim 130 opens, "From the depths I call You." Ibn Ezra (a Torah commentator from Spain, about 900 years ago) says the depths are the exile of Israel, with its poverty and low standing. Radak says that if God kept our sins, we would almost be finished and lost.
Ibn Ezra on Tehillim 130:1; Radak on Tehillim 130:3
כִּי עִמְּךָ הַסְּלִיחָה לְמַעַן תִּוָּרֵא.
For with You is the forgiveness so that You are held in awe
What it means
For forgiveness is with You, so that You will be held in awe.
לֺא כַחֲטָאֵינוּ תַּעֲשֶׂה לָּנוּ וְלֹא כַעֲוֺנֹתֵינוּ תִּגְמֹל עָלֵינוּ.
Not according to our sins should You deal with us and not according to our wrongdoings should You repay us
What it means
Do not deal with us according to our sins, and do not repay us according to our wrongdoings.
In Tehillim 103:10 both verbs are in the past: God "has not dealt" with us as our sins deserve. The siddur changes both to the future form (ta'aseh, tigmol), so the line reads as a request. Radak says the Tehillim verse means that even in exile God did not give us what our sins deserve, which would be destruction.
Tehillim 103:10; Radak on Tehillim 103:10
אִם עֲוֺנֵינוּ עָנוּ בָנוּ יְיָ עֲשֵׂה לְמַעַן שְׁמֶךָ.
If our wrongdoings testify against us, Hashem, act for Your Name's sake
What it means
Though our wrongdoings testify against us, Hashem, act for the sake of Your Name.
Yirmiyahu (the prophet Jeremiah) 14 opens "about the droughts." Radak says Yirmiyahu counts himself in with the people although he had done no wrong, and that rain stopping in our land but not in other lands is what "testifies" against us. The verse goes on, "for our rebellions are many"; the siddur stops before it.
Yirmiyahu 14:1 and 14:7; Radak on Yirmiyahu 14:7
זְכָר רַחֲמֶיךָ יְיָ וַחֲסָדֶיךָ כִּי מֵעוֹלָם הֵמָּה.
Remember Your mercies, Hashem, and Your kindnesses, for they are from forever
What it means
Remember Your mercies, Hashem, and Your kindnesses, for they have been there from forever.
יַעֲנֵנוּ יְיָ בְּיוֹם צָרָה יְשַׂגְּבֵנוּ שֵׁם אֱלֺהֵי יַעֲקֹב.
May Hashem answer us on the day of trouble; may the Name of the God of Yaakov lift us to safety
What it means
Why "the God of Yaakov" and not Avraham or Yitzchak? Radak says Yaakov saw more trouble than they did. He cites a midrash (an early collection of the rabbis' teachings) that notes only Yaakov is named here. So David tells Israel: the One who answered your father Yaakov will answer you.
Radak on Tehillim 20:2; Bereishit 35:3
יְיָ הוֹשִׁיעָה הַמֶּלֶךְ יַעֲנֵנוּ בְיוֹם קָרְאֵנוּ.
Hashem, save! May the King answer us on the day we call
What it means
Rashi says Tehillim 20 is about David staying in Jerusalem to pray while Yoav (his army commander) and the army went to war.
Rashi on Tehillim 20:2
אָבִינוּ מַלְכֵּנוּ חָנֵּנוּ וַעֲנֵנוּ כִּי אֵין בָּנוּ מַעֲשִׂים עֲשֵׂה עִמָּנוּ צְדָקָה כְּרוֹב רַחֲמֶיךָ וְהוֹשִׁיעֵנוּ לְמַעַן שְׁמֶךָ.
Our Father, our King, be gracious to us and answer us for we have no good deeds treat us with charity in keeping with Your mercy and save us for Your Name's sake
What it means
Our Father, our King, be gracious to us and answer us, for we have no good deeds. Treat us with charity, in keeping with Your great mercy, and save us for the sake of Your Name.
This line is almost the same as the last line of Avinu Malkeinu, which ends "charity and kindness, and save us." Here it ends "in keeping with Your great mercy, and save us for the sake of Your Name." The Avinu Malkeinu page asks whether "we have no good deeds" is true.
Siddur Sefard, Avinu Malkeinu
אֲדוֹנֵינוּ אֱלֺהֵינוּ שְׁמַע קוֹל תַּחֲנוּנֵינוּ וּזְכָר לָנוּ אֶת בְּרִית אֲבוֹתֵינוּ וְהוֹשִׁיעֵנוּ לְמַעַן שְׁמֶךָ.
Our Master, our God, hear the sound of our pleas and remember for us the covenant of our fathers and save us for Your Name's sake
What it means
Our Master, our God, hear the sound of our pleas, remember for us the covenant of our fathers, and save us for the sake of Your Name.
The Torah has God speak of the covenant with the fathers Himself, in Vayikra 26:42: "I will remember My covenant with Yaakov, and also with Yitzchak, and also with Avraham." Rashi asks why they are listed backward. His answer: Yaakov, the youngest, is worthy on his own. If not, Yitzchak is with him, and if not, Avraham is with him.
Vayikra 26:42; Rashi on Vayikra 26:42
Now words from the prayer of Daniel (Daniel 9):
וְעַתָּה אֲדֹנָי אֱלֺהֵינוּ אֲשֶׁר הוֹצֵאתָ אֶת עַמְּךָ מֵאֶרֶץ מִצְרַיִם בְּיָד חֲזָקָה וַתַּעַשׂ לְךָ שֵׁם כַּיּוֹם הַזֶּה חָטָאנוּ רָשָׁעְנוּ.
And now, my Master, our God, You who took out Your people from the land of Egypt with a strong hand and made Yourself a name that lasts to this day: we have sinned, we have done wrong
What it means
And now, my Master, our God, You who took Your people out of the land of Egypt with a strong hand and made Yourself a name that lasts to this day: we have sinned, we have done wrong.
These lines come near the end of the long prayer of Daniel (a Jewish leader in the Babylonian exile, whose book is in Tanach) in Daniel 9. Rashi says this verse is a confession.
Daniel 9:15; Rashi on Daniel 9:15
אֲדֹנָי כְּכָל צִדְקֹתֶיךָ יָשָׁב נָא אַפְּךָ וַחֲמָתְךָ מֵעִירְךָ יְרוּשָׁלַםִ הַר קָדְשֶׁךָ כִּי בַחֲטָאֵינוּ וּבַעֲוֺנוֹת אֲבֹתֵינוּ יְרוּשָׁלַםִ וְעַמְּךָ לְחֶרְפָּה לְכָל סְבִיבֹתֵינוּ.
My Master, in keeping with all Your righteous acts, please let Your anger and Your fury turn back from Your city Jerusalem, Your holy mountain, for because of our sins and the wrongdoings of our fathers Jerusalem and Your people are a disgrace to all around us
What it means
Metzudat David (a commentary on the later books of Tanach) says Jerusalem is mocked not because You lack power, but because You were angry at our sins. When Your anger turns back, the mocking stops.
Metzudat David on Daniel 9:16
וְעַתָּה שְׁמַע אֱלֺהֵינוּ אֶל תְּפִלַּת עַבְדְּךָ וְאֶל תַּחֲנוּנָיו וְהָאֵר פָּנֶיךָ עַל מִקְדָּשְׁךָ הַשָּׁמֵם לְמַעַן אֲדֹנָי.
And now, our God, hear the prayer of Your servant and his pleas and let Your face shine on Your desolate Sanctuary for Your sake, my Master
What it means
The last words are "for the sake of Adonai." Rashi says this means for the sake of the holy Name that is called on the Temple, and he points to Shemot 15:17: "the Sanctuary, Adonai, that Your hands made."
Rashi on Daniel 9:17

How to say it

Stand, and say it slowly and with attention, not rushed. The Shulchan Aruch (the main code of Jewish law) says to say it aloud. The Rema (Rabbi Moshe Isserles, who added Ashkenazi customs to it) says quietly. The Mishnah Berurah (a commentary on it from around 1900) adds: as quietly as the Amidah.

Shulchan Aruch and Rema, Orach Chaim 134:1; Mishnah Berurah 134:2, 134:5

The story

Three elders on three ships

The siddur's own note says a midrash (an old collection of the rabbis' teachings) tells it this way. A king seized three elders and put them on three ships with no one steering, then sent them out to sea. The ships were scattered far apart. Where they landed, they were treated harshly. They stood and prayed, and each composed a part of this prayer. The king who had oppressed them died of terrible diseases. The elders sent the prayer to Jewish communities everywhere, to say on Mondays and Thursdays.

Siddur Sefard, note before Vehu Rachum

Or was it a fire?

The Kol Bo (a collection of laws and customs from the Middle Ages) tells it differently. Jews on a ship are told by a governor that he will test them in a furnace, like Hananiah, Mishael and Azariah in the book of Daniel. They ask for 30 days and fast. An old man dreams of a verse he cannot place, and an elder tells him it is Yeshayahu 43:2: "when you walk through fire you will not be burned." He goes into the fire. It splits in three, and three righteous men appear inside it to meet him. They praise God with Vehu Rachum.

Kol Bo 18

Almost every line is a verse, and some were changed

The first line is Tehillim 78:38. Most of what follows comes from Tehillim, Yirmiyahu and Daniel. But the verses were adjusted. In Tehillim 40:12 David says God's mercy will not be held back "from me." Here it says "from us." Tehillim 20:2 says "may Hashem answer you." Here it says "answer us." Tehillim 103:10 reports that God did not treat us as our sins deserve. Here it becomes a request: do not.

Tehillim 78:38, 40:12, 20:2, 103:10

The second half is Daniel's prayer

From "And now, my Master, our God" to the end of this part, the words are Daniel 9:15 to 9:17. Daniel says that in the first year of King Darius he was studying the books and found Yirmiyahu's word that Jerusalem would lie desolate for seventy years. Then he turned to God in prayer "with fasting, sackcloth and ashes." This part ends with his plea that God let His face shine on the Temple, which lay desolate. The prayer goes on with the next verses of Daniel.

Daniel 9:1-3 and 9:15-17

Stand up for this one

The Beit Yosef (Rabbi Yosef Karo's commentary on the Tur, a law code from the 1300s) quotes a rabbi who writes, in the name of the Geonim (the heads of the great Babylonian academies), that Vehu Rachum was set to be said aloud and standing: "this is how we accepted it on ourselves and our children forever." Whoever breaks these rules, he writes, is a fence-breaker.

Beit Yosef, Orach Chaim 134

What was said before

The Tur (a law code from the 1300s) says that in Seder Rav Amram (a prayer book from Babylonia in the 800s, one of the oldest that survive), the custom was to say "If our sins testify against us," a confession, and the passage beginning "Vaya'avor" (the Thirteen Attributes of Mercy). But in the lands the Tur knew, people said only Vehu Rachum, as written in the siddurim. The Mishnah Berurah (a commentary on the Shulchan Aruch from around 1900) adds that some places say the Thirteen Attributes and a confession before it.

Tur, Orach Chaim 134; Mishnah Berurah 134:1

Hard questions

Why only Mondays and Thursdays? Is God more available on those days?

The sources do call Monday and Thursday "days of favor." But several of the reasons they give start with ordinary life, not heaven.

The Gemara (the rabbis' discussions built on the Mishnah) says the prophets set up the Torah reading on Shabbat, Monday and Thursday, so that people would never go three days without hearing Torah. It says Ezra set the courts to meet on Monday and Thursday too, because many people came into town on those days to hear the reading.

Then comes a question about the reason itself. Tosafot (medieval commentators on the Gemara) ask why those two days were chosen. They answer from a midrash: Moshe went up Mount Sinai on a Thursday to receive the second set of tablets and came down on a Monday, and God was appeased. That was a time of favor, so those days were fixed. This is also why people used to fast on Mondays and Thursdays. The Tur (a law code from the 1300s) gives the same reason.

The Kol Bo (a collection of laws and customs from the Middle Ages) adds another thought. On Monday and Thursday the court in heaven and the court on earth are alike, so these are days of mercy.

Tosafot go on to check the dates and admit the weekdays fit neatly only on one rabbi's count of the calendar. For the others they need a workaround.

So there are layers. The Gemara ties the days to the community's calendar: reading and courts. Tosafot and the Tur add Moshe's days of favor, and with them the fasting and the extra pleading.

Bava Kamma 82a,Tosafot on Bava Kamma 82a,Tur, Orach Chaim 134,Kol Bo 18

There are two different stories about who wrote this. Which one is true?

The honest answer is that nobody can check either one. Here is what the sources do say.

The siddur's own note tells of a king, three elders on three ships with no one steering, and a prayer sent out to Jewish communities. The Kol Bo tells of a governor who threatens to throw Jews into a furnace, thirty days of fasting, an old man who walks into a fire, and three righteous men who appear inside the fire to meet him. The details are different. In both, three elders stand behind the prayer, and in both it ends up set for Mondays and Thursdays.

The Mishnah Berurah says the prayer was set up through "a great miracle," as the Kol Bo records and as the siddurim print. Rabbi Yosef Karo (who also wrote the Shulchan Aruch) says the same in the Beit Yosef.

Here is what can be checked. The first line is a verse, Tehillim 78:38, and most of the rest comes from Tehillim, Yirmiyahu and Daniel. So the words are older than any story about the elders. The stories are about who gathered them into this prayer and why we say it on these days. (The same verse is said earlier in the morning too, in Romemu. The Romemu page tells where it comes from in Tehillim.)

So the story is a tradition. It is recorded in medieval books, printed in siddurim, and accepted by the Mishnah Berurah. The verses are what you can open and read yourself.

Siddur Sefard, note before Vehu Rachum,Kol Bo 18,Beit Yosef, Orach Chaim 134,Mishnah Berurah 134:2

Why does the prayer say God forgives "so that You will be feared"?

The line is from Tehillim 130. In the prayer it reads: "If You kept a record of sins, God, who could stand? But with You is forgiveness, so that You will be feared." It sounds backwards, because you would expect forgiveness to make people less afraid. (The Hebrew word can mean feared or held in awe.) The commentators noticed and gave two answers.

The first answer is about despair. The Meiri (a commentator from Provence, around 1300) says people cannot avoid sinning, because the heart's pull toward wrong is strong. If a person sins and believes there is no way back, he gives up. Why bother being careful, he thinks, if nothing helps? Ibn Ezra (a commentator from the 1100s) says the same: without forgiveness, people would not fear God and would do whatever they wanted. Forgiveness is what keeps a person trying.

The second answer is about who forgives. Rashi (the main medieval commentator, France, died 1105), Radak (Rabbi David Kimchi, Provence, died around 1235) and Metzudat David (a line-by-line commentary on Tanach from the 1700s) read "with You" to mean with You alone. In the Torah, God says of the angel He sends before the people: "he will not pardon your offenses" (Shemot 23:21).

Radak, quoting his father, says that otherwise people might tell themselves that if they sin, the angels will be calmed and forgive. Metzudat David says the same: a person would be tempted to rely on a messenger, and fear of God would shrink. Forgiveness stays with God alone, so that people fear Him and not a go-between.

These are two answers to one oddly worded line. The verse before it asks who could stand. This one answers that there is forgiveness.

Tehillim 130:3-4,Meiri on Tehillim 130:4,Ibn Ezra on Tehillim 130:4,Radak on Tehillim 130:4,Metzudat David on Tehillim 130:4,Shemot 23:21

Sparks

Short ideas from the Chassidic masters, the Kabbalah and the Mussar teachers.

Ramban

Forgiveness is a help to serve God

The Ramban (Rabbi Moshe ben Nachman, a medieval Torah commentator who died in 1270) explains why Moshe opened the Book of Devarim by recalling Israel's sins and God's mercy. Moshe did not want the people to think: nobody is without sin, so judgment will crush us at once and we can never enter the Land. So he told them that God is full of mercy, and that His forgiveness is "a support and a help to people in serving Him." He then quotes a verse (Tehillim 130:4) that this prayer also uses: "With You is forgiveness, so that You will be feared."

כי הסליחה והמחילה ממנו יתברך סיוע ועזר לבני אדם בעבודתו. וכענין שאמר הכתוב כי עמך הסליחה למען תורא

Ramban on Devarim, Introduction

Chassidut

Judged by where you are headed

Rabbi Shmuel Bornstein of Sochatchov (a Chassidic rebbe in Poland, who died in 1926) suggests that one side of God's judging looks at the end of the story, not only at the present. He calls that part of God's mercy. If the future will be good because of what God helps a person earn today, then "He is merciful and forgives sin." Then he gives a picture: people give a poor merchant goods on credit so he can trade, but not a man who only sits with folded hands. God, he says, does the same for anyone who at least wants to grow.

וזהו מרחמי הש"י שלא להשגיח על ההוה אלא על העתיד, ואם עכ"פ העתיד יהי' טוב ע"י מה שמזכהו עכשיו אז והוא רחום יכפר עון

Shem MiShmuel, Parashat Tazria (Rosh Chodesh Nisan)

Chassidut

Forgiveness takes the curtain down

Rabbi Shlomo of Radomsk (a Chassidic master in Poland, who died in 1866) starts from the idea that every Jewish soul is a piece of God from above, and a person should stay attached to his source like a branch to a tree. When a person does not go the straight way, he writes, sins become a curtain that separates. So "with You is forgiveness" means: we ask God to forgive us so that we can be "with You," close to You, with no curtain between us and God. Now read "with You" again.

וז"פ כי עמך הסליחה. היינו שמתפללים להש"י שיסלח לעוונותינו כדי שנוכל להיות עמך בדביקות שלא יהי' חלילה שום מסך המבדיל בינינו לבין הש"י

Tiferet Shlomo, on the Festivals, Erev Yom Kippur 7

Zohar

A prayer that is not complete gets chased

The Zohar (the central book of Kabbalah) says that if a prayer is not complete, many angels of harm run after it, as the Book of Eichah (Lamentations) says: "All her pursuers overtook her." That, it says, is why we say this verse. It matches the four phrases of the verse to four harmful forces, so that they do not chase the prayer. The next lines describe the other case: a prayer that rises whole, wrapped in a mitzvah and with tefillin on the head and arm, and the angels of harm run away.

ואי צלותא לאו איהי שלימא, כמה מלאכי חבלה רדפין אבתרה ... ובגין דא מצלין והוא רחום יכפר עון

Zohar, Parashat Bereishit (Sulam paragraph 184)

Halacha

The practical laws. For a final ruling, ask your rav.

What if I said it sitting down?

The Shulchan Aruch (the main code of Jewish law) says to say Vehu Rachum standing. Someone who does not has broken the Sages' enactment and is called a "fence-breaker." The Mishnah Berurah (a central commentary on daily law, written around 1900) brings a view that this label fits only someone who skipped it altogether, not someone who said it sitting. The Kaf HaChaim (a Sephardic law commentary from the early 1900s) records the same view.

Shulchan Aruch, Orach Chaim 134:1; Mishnah Berurah 134:3; Kaf HaChaim, Orach Chaim 134:3

Do I have to fast on Mondays and Thursdays?

The Rema (Rabbi Moshe Isserles, who added Ashkenazi practice to the Shulchan Aruch) says the custom is to fast on these days, since they are days of favor. The Arukh HaShulchan (a law code from around 1900) explains: when fasts are declared, they fall on Mondays and Thursdays. The Shulchan Aruch reports only one view of a decree to fast every week. On it, the Mishnah Berurah adds that someone who cannot fast should at least pray on these days about the Temple, the burned Torah and the shame to God's name.

Rema, Orach Chaim 134:1; Arukh HaShulchan, Orach Chaim 134:2; Shulchan Aruch, Orach Chaim 580:3; Mishnah Berurah 580:16

There is a bris or a groom in the synagogue. Do I skip it?

The sources say yes. At a bris (circumcision), the Arukh HaShulchan (a law code from around 1900) says Tachanun and Vehu Rachum are skipped for everyone present, and no one needs to make it up later at home, because of the joy. The Mishnah Berurah (a central commentary on daily law) says the same for the seven days of a groom's celebration, whenever he is in the shul. On a public fast day with a bris, the Shulchan Aruch says the confession and forgiveness prayers are said, but not Vehu Rachum.

Arukh HaShulchan, Orach Chaim 131:15; Mishnah Berurah 131:26; Shulchan Aruch, Orach Chaim 131:5

I am praying in a shiva house. Do I say it?

The Arukh HaShulchan (a law code from around 1900) says Vehu Rachum is not said on Mondays and Thursdays in a house of mourning (shiva is the seven days of mourning), so as not to add strict judgment where it already weighs on the family. Those who prayed there say it when they get home. The Mishnah Berurah (a central commentary on daily law) agrees, but notes that some are lenient about saying it later. Falling on your face is not made up at home.

Arukh HaShulchan, Orach Chaim 131:14; Mishnah Berurah 131:20

Do girls say Vehu Rachum?

Peninei Halakhah (a modern guide to Jewish law by Rabbi Eliezer Melamed) rules that women are exempt from everything men customarily say after the Amidah, and names Tachanun, Ashrei and others in that list. It does not name Vehu Rachum, so this is the closest ruling we found. The reason it gives: even men have no strict obligation to say these, only a custom that became binding, and women never took it on. A woman who wants to say them may.

Peninei Halakhah, Women's Prayer 17:1

Do I say it all month in Nisan?

The Shulchan Aruch (the main code of Jewish law) rules that no one falls on their face in prayer all month in Nisan. The Shulchan Aruch HaRav (the code of Rabbi Shneur Zalman of Liadi, the first Chabad Rebbe) writes that in his countries the custom all of Nisan is no Tachanun, and no Vehu Rachum on Mondays and Thursdays. The Chok Yaakov (a commentary on the laws of Pesach from around 1700) quotes an older book of customs that says the same: no Vehu Rachum in Nisan.

Shulchan Aruch, Orach Chaim 429:2; Shulchan Aruch HaRav, Orach Chaim 429:8; Chok Yaakov, Orach Chaim 429:7

Sources

Show the 10 sources quoted on this page

Siddur Sefard, note before Vehu Rachum
ויש במדרש דג' זקנים תקנוהו. שתפשם מלך אחד ונתנם בג' ספינות בלא מנהיג. ושלחם לים ונתפזרו למרחקים.
And there is a midrash that three elders set it up. A king seized them and put them in three ships with no one steering. He sent them out to sea and they were scattered far away.
Kol Bo 18
והנהו תלת סבי בכן שבחו ... ותקונהו לאמרו בשני ובחמישי שהוא יומא דדינא.
Those three elders then praised God... and they set it to be said on Mondays and Thursdays, which is a day of judgment.
Tosafot on Bava Kamma 82a
משה רבינו ע"ה עלה בחמישי לקבל לוחות האחרונות וירד בשני ונתרצה לו המקום ולפי שהיה עת רצון באותה עלייה וירידה קבעו בשני וחמישי
Moshe went up on Thursday to receive the last tablets and came down on Monday, and God was appeased. Because that going up and coming down was a time of favor, they fixed Monday and Thursday.
Bava Kamma 82a
כֵּיוָן שֶׁהָלְכוּ שְׁלֹשֶׁת יָמִים בְּלֹא תּוֹרָה, נִלְאוּ, עָמְדוּ נְבִיאִים שֶׁבֵּינֵיהֶם וְתִיקְּנוּ לָהֶם שֶׁיְּהוּ קוֹרִין בַּשַּׁבָּת... וְקוֹרִין בְּשֵׁנִי... וְקוֹרִין בַּחֲמִישִׁי... כְּדֵי שֶׁלֹּא יָלִינוּ שְׁלֹשָׁה יָמִים בְּלֹא תּוֹרָה.
Once they had gone three days without Torah, they grew weary. The prophets among them set up for them a Torah reading on Shabbat... on Monday... and on Thursday... so that they would never spend three days without Torah.
Tehillim 130:3-4
אִם עֲוֺנוֹת תִּשְׁמָר יָהּ אֲדֹנָי מִי יַעֲמֹד. כִּי עִמְּךָ הַסְּלִיחָה לְמַעַן תִּוָּרֵא.
If You kept a record of sins, God, who could stand? But with You is forgiveness, so that You will be feared.
Meiri on Tehillim 130:4
שבני אדם אי איפשר להם שלא לחטוא כי יצר לב האדם רע ואלו לא הבטחת בסליחה לא היית נורא כי כשחטא האדם כבר נואש מן הסליחה
People cannot help sinning, because the heart's pull is toward wrong. If You had not promised forgiveness, You would not be feared, because a person who has sinned would already have given up on being forgiven.
Radak on Tehillim 130:4
למה שלא יאמרו בני אדם בלבם אם אנו חוטאים יתפייסו לנו המלאכים וישאו לפשעינו
So that people will not say in their hearts: if we sin, the angels will be calmed for us and will forgive our wrongs.
Daniel 9:2
אני דניאל בינתי בספרים מספר השנים אשר היה דבר ה׳ אל ירמיה הנביא למלאות לחרבות ירושלם שבעים שנה
I, Daniel, studied the books and worked out the number of years that, by the word of Hashem to Yirmiyahu the prophet, Jerusalem would lie in ruins: seventy years.
Beit Yosef, Orach Chaim 134
בשם הגאונים שתיקנו לומר והוא רחום בקול רם ומעומד ואמרו הכין קבלנו עלינו ועל בנינו לעולם וכל העובר על התקנות פורץ גדר
In the name of the Geonim, who set Vehu Rachum to be said aloud and standing, saying: this is how we accepted it on ourselves and our children forever, and whoever breaks these rules is a fence-breaker.
Mishnah Berurah 134:2
ותיקון אמירתה היה ע"י מעשה נס גדול כמובא בכל בו ונדפס בסידורים. וצריך לאמרו בכונה ובמתון ולא במרוצה.
Its being set up came through a great miracle, as the Kol Bo records and the siddurim print. It must be said with focus and slowly, not at a run.

Every prayer in the siddur