Midrasz do Sofoniasza 2:1

(Fol. 19) "The king must not act as a judge, nor be summoned before court." R. Joseph said: This is concerning the kings of Israel; but the kings of the house of David may act as a judge, and can be summoned before court, as it is written (Jer. 21, 12) O house of David, thus said the Lord: Exercise justice on every morning. And if they were not be summoned before court, how could they judge? Behold! it is written (Zeph. 2, 1) Gather yourself together. And Resh Lakish said: "This means first correct thyself, then correct others." Why then is it prohibited to the Kings of Israel? Because of the incident which happened with the slave of King Janai, who murdered a person. Simon b. Shetach said to the sages: "Notwithstanding that he is the slave of the king, he must be tried." They sent word to the king: "Your slave has killed a man." And Janai sent his slave to them to be tried. Whereupon they sent to him: "You also must appear before the court, for the Torah says (Ex. 21, 29) Warning has been given to its owners — i.e., the owner of the ox must appear at the time the ox is tried." He then came and took a seat. "Arise King Janai," said Simon b. Chetach, "so that the witnesses shall testify while you stand; yet not for us do you rise, but for Him who commanded and the world came into being, as it is said (Deut. 19, 17) Stand before the Lord." And the king answered: "It must not be as you say, but as the majority of your colleagues shall decide." (Ib. b) Simon then turned to his right, but they cast their eyes down (were afraid to give their opinion). He turned to his left, and they also cast their eyes down. Simon b. Shetach exclaimed: "You are entertaining consideration [of fear] in your mind! May the One who knows [man's] thoughts take revenge upon you." Thereupon Gabriel came and smote them to the floor, and they died. At that time the sages decreed that a king should neither act as a judge nor appear before court; neither be a witness, nor can anyone testify against him.

“Let us search and examine our ways, and return to the Lord. Let us lift up our heart with our hands to God in the heavens” (Lamentations 3:40–41).
“Let us search and examine our ways, and return to the Lord. Let us lift up our heart with our hands to God in the heavens” – Rabbi Beiva bar Zavdai, Rabbi Tanḥum bar Ḥanilai, and Rabbi Yoshiya went out for a fast.⁶⁵On fast days, the congregation would take the ark out to the city square and pray there. See Mishna Taanit 2:1. Rabbi Beiva bar Zavdai expounded and said: Is it possible that a person’s heart is taken from him and returns to him?⁶⁶What, then, is the meaning of the verse “Let us lift up our heart with our hands”? Rather, we should focus our hearts on our hands,⁶⁷We must ensure that our hands have not engaged in malfeasance with another’s property. and only thereafter to God in the heavens. If there is a swarming creature in a person’s hand, even if he immerses himself in all of the primordial waters, he will never be purified. If he casts the swarming creature from his hand, his immersion is effective for him [even] in forty se’a.
Rabbi Tanḥuma expounded: “The princes of Israel and the king humbled themselves and said: The Lord is righteous” (II Chronicles 12:6). And it is written: “When the Lord saw that they had humbled themselves, the word of the Lord was with Shemaya, saying: They have humbled themselves; I will not destroy them, and I will grant them a small measure of deliverance, and My wrath will not be poured upon Jerusalem by means of Shishak” (II Chronicles 12:7). It is not written here, “when the Lord saw that they had fasted,” but rather, “that they had humbled themselves.”
Rabbi Yoshiya expounded: “Gather yourselves, gather [hitkosheshu vakoshu]” (Zephaniah 2:1) – let us adorn [nekashet] ourselves and thereafter adorn others. Because there is a person who is here who slandered me before Rabbi Yoḥanan; let the entire people stand for judgment.⁶⁸He demanded that the individual who had slandered him repent before exhorting others to do so, and so too that each person repent from his sins. They said: Rabbi Ḥiyya, Rabbi Ami, and Rabbi Yosei were there. They stood and went out.⁶⁹Some explain that it is because they were the guilty parties and they were angry that he had called them out (Yefe Anaf). Others explain that they sought to spare the guilty party the public shame (Matnot Kehuna).
“We have transgressed and defied; You have not forgiven” (Lamentations 3:42).
“We have transgressed and defied [umarinu]” – the Rabbis there⁷⁰In Babylon said: When the endives are bitter [meriran], the vinegar is sour.⁷¹This translation is based on the interpretation of Rabbi David Luria. He explains that the endives are dipped in the vinegar. The point is that Israel sinned, and so too God was strict in exercising judgment. There are alternate interpretations of this line in the midrash; see, e.g., Matnot Kehuna. The Rabbis here⁷²In the Land of Israel said: If actions are evil, they are harsh for the one who performs them. Rabbi Huna said in the name of Rav Yosef: “We have transgressed and defied” – as is our wont. “You have not forgiven” – is that Your wont? Rabbi Levi said: “We have transgressed and defied” – and You destroyed Your Temple.⁷³As “You have not forgiven.”

Raba b. R. Huna possessed a forest on the shore of a river, and when he was asked to cut it down he answered: "Let the forests which are before and behind mine be cut down, and then I will cut down mine." But how could he answer so? Is it not written (Zeph. 2, 1) Gather yourselves together. And Resh Lakish said: This means "Correct thyself first, and then others." The forests before and behind him belonged to a governor of the Persians, Parzak (Fol. 108), and Rabba was aware that he would not agree to cut down his, consequently the carriers of the boats could not pass anyhow; and what would be the use of cutting down his own? Rabba b. R. Nachman was sailing a boat, and had seen a forest on a shore, and to the question. Whose is it? he was told that it was Rabba b. R. Huna's. Rabba b. R. Nachman applied to him the verse (Ezra 9, 2) And the hand of the princes and the rulers hath been the first in this trespass, and ordered his people to cut it down. When Rabba b. R. Huna came and found them cutting, remarked: "He who has cut this, his own branches shall be cut off." And it was said that during all the years of the existence of Rabba b. R. Huna the children of Rabba b. R. Nachman did not live long.