Midrash for Ruth 2:4

...And in Jonah it is written, "I would rather die than live." Jonah was the son of the woman of Zarfat. He had already died once, and knew that he would have rest, and Elijah did not die. And so he said, "am I not better than my ancestors?"

Said R. Joshua b. Levi: "Three things were done by the worldly court, and the heavenly court agreed with them. They are: The reading of the Book of Esther on Purim (Feast of Esther); greeting with the Holy Name, and placing the tithe belonging to the Levites in the treasury of the sanctuary. As to the first, we infer from (Esther 9, 27) The Jews ordained, and took upon them; i.e., they ordained above, what they took upon them down below. Greeting, from (Ruth, 2, 4) And he said unto the reapers, the Lord be with you, and there is also a verse (Jud. 6, 12) The Lord is with thee, thou mighty man of valor. To what purpose is the second quotation? Lest one say that Boas did it according to his own opinion and without the consent of heaven. Come, listen! The Lord is with thee, thou mighty man of valor. And concerning tithe, as it is written (Mal. 3, 10) Bring ye the whole tithes into the store-house, that there may be food in My house, and try Me now herewith, saith the Lord of hosts, if I will not open you the windows of heaven, and pour you out a blessing, that there shall be more than sufficient.

“Behold, Boaz came from Bethlehem, and he said to the reapers: May the Lord be with you. They said to him: May the Lord bless you” (Ruth 2:4).
“Behold, Boaz came from Bethlehem” – Rabbi Tanḥuma said in the name of the Rabbis: There are three matters that the earthly court decreed and the supernal court agreed with them, and these are: To greet another with the name of God, the Scroll of Esther, and tithes. Greeting others, from where is it derived? It is as it is stated: “That think to cause My people to forget My name” (Jeremiah 23:27). When did they think to do so? It was during the days of Atalyahu. The Rabbis say: It was during the days of Ḥananya, Mishael, and Azarya. Rabbi Ḥananya said in the name of Rabbi Yehuda ben Rabbi Simon: It was during the days of Mordekhai and Esther. But Boaz and his court had arisen and instituted to greet another with the name of God, as it is stated: “Behold, Boaz came from Bethlehem, and he said to the reapers: May the Lord be with you.” Likewise, the angel said to Gideon: “The Lord is with you, mighty man of valor” (Judges 6:12).
The Scroll of Esther, from where is it derived? Rabbi Yirmeya said in the name of Rabbi Shmuel bar Yitzḥak: What did Mordekhai and Esther do? They wrote letters and sent them to all the residents of the Diaspora: Do you accept upon yourselves “to observe these two days” (Esther 9:27)? [The residents of the Diaspora] sent and said [in response]: Are our problems with Haman not enough, that you impose upon us to observe these two days?¹⁵⁴They were afraid that their celebration would arouse the ill will of the gentiles. They said to them: If you are afraid of this matter, it is written among the volumes, as it is stated: “[All the acts of his power and his might, and the full account of the greatness of Mordekhai, how the king advanced him,] are they not written in the book of chronicles [of the kings of Media and Persia]?” (Esther 10:2). What did they do? They wrote a second letter and sent it to them, “this second letter of Purim” (Esther 9:29).
Rabbi Ḥelbo said in the name of Rabbi Shmuel bar Naḥman: There were eighty-five elders, among them thirty-plus prophets who were distressed over this verse: “These are the commandments that the Lord commanded Moses” (Leviticus 27:34) – “these” [indicates that] one may not add and one may not subtract, and a prophet is not permitted to introduce anything new from now on; and Mordekhai and Esther are asking us to take upon ourselves something new? [They were distressed] until the Holy One blessed be He enlightened them and they found it written in the Torah, in the Prophets, and in the Writings:¹⁵⁵They found an allusion to the writing of the book of Esther, and therefore were no longer concerned that the observance of Purim was considered a forbidden addition to the Torah. In the Torah, as it is written: “Write this as a memorial in the book” (Exodus 17:14). In the Prophets, as it is written: “They who feared the Lord spoke one with another; and the Lord heeded, and heard, and it was written in the book [of remembrance]” (Malachi 3:16). In the Writings, as it is written: “Are they not written in the book of chronicles” (Esther 10:2). Rav, Rabbi Ḥanina, Rabbi Yonatan, bar Kappara, and Rabbi Yehoshua ben Levi said: This scroll was not stated by the court,¹⁵⁶It was not the court in the time of Mordekhai and Esther that first introduced the book of Esther. but rather was stated at Sinai, but there is no chronological order to the Torah.¹⁵⁷Therefore, it does not appear in writing until the book of Esther. From where is it derived that the Holy One blessed be He agreed with them? Rav said: “The Jews fulfilled and received [vekibbelu]” (Esther 9:27), vekibbelu (pl.) is not written, vekibbel (sing.) is written; the master of the Jews received it.¹⁵⁸The word vekibbelu is written without the concluding vav, such that it can be read in the singular. This is an allusion to the fact that Moses received it at Sinai.
Tithes, from where are they derived? It is as Rabbi Berekhya said in the name of Rabbi Keritzeppa: Due to the sin of [failing to separate] teruma and tithes, they were exiled. Shimon bar Abba said in the name of Rabbi Yoḥanan: When they were exiled they were exempted, and they obligated themselves. What did the members of the Great Assembly do? They wrote a scroll¹⁵⁹Stating that they were obligating themselves to separate teruma and tithes even though they were exempt by Torah law. and unfurled it in the Temple courtyard, and in the morning they found it signed; that is what is written: “For all this we make a covenant, and write it, and it is signed” (Nehemiah 10:1). One verse says: “It is signed [al heḥatum (sing.)]” (Nehemiah 10:1), and one verse says: “It is signed [al haḥatumim (pl.)]” (Nehemiah 10:2). How so? Rather, al heḥatum is the supernal court, and al haḥatumim is the earthly court. Some say, the proscription of Jericho as well:¹⁶⁰Following the capture of Jericho, Joshua declared all its spoils proscribed. So said the Holy One blessed be He to Joshua: “Israel has sinned [and they have even transgressed My covenant; they have also taken from the proscribed spoils]” (Joshua 7:11). Was it not Joshua who issued the decree? This teaches that the Holy One blessed be He, too, agreed with him.¹⁶¹When one of the Israelites took from the spoils, God said that they had “transgressed My covenant.”