Мидраш к Берешит 8:9

“And great enslavement,” Rabbi Aḥa said: Because they would keep the Hebrew slave in servitude, just as it says: “At the end of seven years [each of] you shall free [his Hebrew brother]” (Jeremiah 34:14).
“She settled among the nations, did not find rest,” Rabbi Yudan ben Rabbi Neḥemya said in the name of Rabbi Shimon ben Lakish: Had she found rest, she would not have returned. Similarly, “the dove did not find rest” (Genesis 8:9). Similarly, “among these nations you will not be calm, and there will be no rest for your foot” (Deuteronomy 28:65).
“All her pursuers have overtaken her within the straits [hametzarim].” This is like what we learned, the statement of ben Nanas: By her demarcations and her borders [uvmetzranav].⁸⁸Mishna, Bava Batra 7:3. The midrash cites this mishna to explain the Hebrew term employed in the verse in Lamentations. The word hametzarim, the straits, is understood to mean within her borders.
Another matter, “All her pursuers have overtaken her within the straits,” in days of distress, between the seventeenth of Tamuz and the ninth of Av,⁸⁹The walls of Jerusalem were breached on the seventeenth of Tamuz and the Temple was ultimately destroyed on the ninth of Av (Mishna, Taanit 4:6). during which Ketev Meriri⁹⁰This is the name of a destructive demon. See Pesaḥim 111b. is prevalent, just as it says: “Nor the pestilence that stalks in darkness, nor the destruction [ketev] that lays waste at noon” (Psalms 91:6). Rabbi Abba bar Kahana and Rabbi Levi, Rabbi Abba bar Kahana said: It passes through during the main time of sunlight,⁹¹The part of the day when the sun is strongest. from the beginning of the sixth hour until the end of the ninth.⁹²These are halakhic hours. In this system, the daylight hours are divided into twelve equal parts. Rabbi Levi said: It passes through the main part of the day, from the end of the fourth hour until the beginning of the ninth. It does not pass through the sunlight or the shade, but rather through the shade adjacent to the sunlight.
Rabbi Yoḥanan and Rabbi Shimon ben Lakish, Rabbi Yoḥanan said: It is completely full of eyes, scales, and hair. Rabbi Shimon ben Lakish said: One eye is situated on its heart, and anyone who sees it falls and dies. There was an incident involving a certain pious man who saw it and he fell on his face and died. Some say it was Yehuda ben Rabbi [Yehuda Hanasi]. Shmuel saw it and did not fall. He said: It is [just] a house snake.
Rabbi Abahu was sitting and studying in a synagogue in the area of Caesarea. He saw a certain person who was carrying a stick and going to strike another person. He saw a demon standing behind him carrying an iron rod. [Rabbi Abahu] stood and called out to him, saying to him: ‘Why do you seek to kill your counterpart?’ [The man] said to him: ‘Can a person kill another with this?’ He said to him: ‘There is a demon standing behind him that is carrying an iron rod. You strike him with this and it will strike him with that and he will die.’
Rabbi Yoḥanan would instruct the teachers of Bible and the teachers of Mishna not to raise a strap to the children during those days.⁹³The days between the seventeenth of Tamuz and the ninth of Av. Rabbi Shmuel bar Naḥmani would instruct the teachers of Bible and the teachers of Mishna to dismiss the children during those four hours.⁹⁴He did not want the teachers to instruct the children at all during the four hours when Ketev Meriri is active in the world, lest the teachers strike the students, which could lead to danger due to the demon.

And again [Noach] sent forth the dove out of the ark . . . And the dove came in at evening, and here, an olive leaf torn off in her mouth” [Gn 8:11]. “An olive leaf torn off in her mouth”—From where did she bring it? R’ Bibi said: The gates of Gan Eden were opened for her, and from there she brought it. Said R’ Abahu: Had she brought it from Gan Eden, couldn’t she bring something special, cinnamon or balsam? But she gave [Noach] a hint, and said to Noach: Better is bitterness from this and not sweetness from beneath your hand.