(15) So she said, “See, your sister-in-law has returned to her people and her gods. Go follow your sister-in-law.” (16) But Ruth replied, “Do not urge me to leave you, to turn back and not follow you. For wherever you go, I will go; wherever you lodge, I will lodge; your people shall be my people, and your God my God.

See, your sister-in-law has returned, that is, after she returned to her people, she also returned to her gods. As it says in the Midrash, when she returned to her people, she returned to her gods, because her mind was not set on joining the Jewish religion, and perhaps your mind, too, [Ruth], and if so, you should return with her.

Naomi, her mother-in-law, said, "My daughter, have I not sought out for you peace, which will be good to you?" It is known that the Holy One does not withhold reward from any creature, whether intentionally facilitated through a mitzvah (i.e. tzedakah) or even unintentionally, still reward finds its way. As the Rabbis have said, if [someone] loses some money, and a poor person finds it, then there is still a reward [for the one who lost the money]. Ruth the righteous was discerning the holy sparks within the land of Moab and was so powerfully grounded in her holiness that the kings of Israel stemmed from her, David and Solomon and all the holy ones, until the Melech Moshiach...

(20) Naomi said to her daughter-in-law, “Blessed be he of the LORD, who has not failed in His kindness to the living or to the dead! For,” Naomi explained to her daughter-in-law, “the man is related to us; he is one of our redeeming kinsmen.” (21) Ruth the Moabite said, “He even told me, ‘Stay close by my workers until all my harvest is finished.’” (22) And Naomi answered her daughter-in-law Ruth, “It is best, daughter, that you go out with his girls, and not be annoyed in some other field.” (23) So she stayed close to the maidservants of Boaz, and gleaned until the barley harvest and the wheat harvest were finished. Then she stayed at home with her mother-in-law. (1) Naomi, her mother-in-law, said to her, “Daughter, I must seek a home for you, where you may be happy.

She stayed close to the maidservants of Boaz, to glean until the close of the harvest season for barley and wheat. R' Shmuel bar Nachmani said that from the beginning of the barley harvest through the end of the wheat harvest comprised three months.

And cleave. And so she did, staying close to the young women in Boaz' employ until the close of the harvest season for wheat and barley. The Midrash says that the span of this period is three months, which map to the three months of distinction, per the law for converts, that they should not get married before [three months have passed after converting]. Thus, it was after the three month harvest that Ruth began seeking a levirate marriage.

She stayed at home with her mother-in-law, that is to say, even though she stayed close for most of the time with the young women in Boaz' employ, that was when she had to be in the field to glean, as it was written, "So she stayed close to the maidservants of Boaz, and gleaned," but after, when the harvesting was over, she returned to her mother-in-law's home and did not linger to spend time with the maidservants, since her love for Naomi superseded her love for anyone else.

(1) Naomi, her mother-in-law, said to her, “Daughter, I must seek a home for you. The commentators explain that while a mother seeks to find another husband for her daughter who has been widowed, it is grievous to a mother-in-law to see her daughter-in- law married to another man in place of her son. When, “Naomi, her mother-in-law, said to Ruth, “My daughter,” she was saying, ‘I am treating you as if you were my own daughter whose husband died and who now seeks to marry to another. So shall I do for you though I am only your mother-in-law.

Some say that, ‘my daughter,’ alludes to what the Kabbalists said: Naomi is the mystery of Leah and Ruth cleaved to her in order to receive the lights of Leah. This is hinted at in the words, biti halo, “My daughter, must I not…” The letters of the word halo, “Must I not…” are the same letters that make up the name of Leah. Since you take from me the aspect of Leah, so you are my daughter.

(1) My daughter, I must seek [a home] for you, meaning, there have already been three months of distinction, and now it rests on me to seek for you some peace. That is, that you may have a spouse, as it is written [prior in Ruth 1:9], "[May G-d grant that each of you] find peace in the house of a husband," who will be good to you. For sometimes, you can find peace in a marital home but which will not be good for you, as when one's spouse does not keep the Torah, then it will not be beneficial to one's spirit. As Chazal have said [of a woman who married a rabbi and helped tie his tefillin to his arm, but then] she married a tax collector and helped tie his tax seals to his hand. What I want for you is that he be good to you, both in terms of [physical] rest coupled with true goodness.

Rabbi Shimon ben Gamliel would say: Anyone who brings peace into their home is regarded by the Torah as if they had brought peace to everyone in Israel. And anyone who brings jealousy and competitiveness into their home is regarded as if they had brought jealousy and competition to all of Israel. For everyone is sovereign in their own home, as it says (Esther 1:22), “So every person shall define their own home.”

...Naomi spoke to her daugher-in-law of two blessings, one greater than the other. The first is to build "one's mother’s house, and will G-d deal kindly with you, as you have dealt with the dead and with me" (Ruth 1:8) The second blessing is higher, that G-d will provide for you to find peace with a life partner... But after the close of the barley and wheat harvests, after the conclusion of the three month period of distinction for converts, [a fallow period] during which neither the first blessing of the mother's house nor that of the peace of finding one's life-partner can be fulfilled; one is left like a poor, bedraggled sort in one's mother-in-law's house, during which there is no doubt that these difficult thoughts did not depart her mind. Then, Naomi came to speak to her heart and actualize even the second, greater blessing, that G-d will help her find peace. This is what scripture meant in saying, "She stayed close to the women in Boaz' employ... until the close of the barley and wheat harvests," the three month period mentioned above, and it seemed as though instead of fulfilling the two promised blessings of a mother's home and of a marital abode, that she would be adrift in a mother-in-law's house. Rather, the Naomi spoke to her comfortingly regarding her being her daughter, that is, if she is worrying about the first blessing of a woman in her mother's house, but in truth, the house of the "mother-in-law" is not anything, for you are my daughter, as it is I who converted you; you are like my own little one that I myself birthed, and now that you are Jewish, I want nothing for you but what I seek for you, the serenity of the second blessing and the goodness with which it can bless you, that is, to find the peace of finding your life-partner.

To leave you, to turn back and not follow you, that is, not that I would ever abandon you, for I do not want to depart from you ever. And further, I would not turn back, because even if I am forced to leave you, I would not return to Moab and turn away from you, as I would still press forward and make my way to Judah and convert there through others... For wherever you go, I will go, that is, do not think that the aim of my journey is different from that of yours, for you are traveling to the place where you can fulfill your religion and keep the Torah and its commandments, even the ones connected to the Land. And I, too, am only going in order to achieve that same goal, for my objective is the same as the one to which you are moving. And do not think that I am hoping for some temporary "success" and marry some rich guy or the like, for where you sleep, I will sleep, like a stranger in the Land, like the righteous, for whom this world is merely a roadside inn. For the true aim of my journey stems from [the truth] that your people are my people, and your G-d is my G-d, for I have already touched the Torah of your G-d and the practices of your people, and it is like I am one of them.