Ruth 3:1-18

Then Naomi her mother in law said unto her, My daughter, shall I not seek rest for thee, that it may be well with thee? And now is not Boaz of our family, with whose maidens you have been working? Behold, he winnows the barley tonight in the threshingfloor. So wash yourself, put on your perfume, and your beautiful gown, and get down to the threshingfloor: but don't let them see you, until they have finished eating and drinking. And it shall be when he lies down to sleep, that you mark carefully where he's lying, and you go in, and uncover his feet, and lay down there; and he will tell you what you're to do. And she said unto her, All that you say to me I will do. So she went down to the floor, and she did according to all that her mother in law had instructed her. And when Boaz had eaten and drunk, his heart was merry, and he went to lie down at the end of the heap of corn: she came very quietly, and uncovered his feet, and laid down. Now about midnight, he woke up, and was afraid; as he was rolling over he became aware of the fact that a woman was lying there at his feet. And he said, Who are you? And she answered, I am Ruth your handmaid: spread therefore thy blanket or covering over thine handmaid; for thou art a near kinsman (Ruth 3:1-9).

Now under the law because God sought to preserve families, if a man married a wife, and died before they had any children, then it was his brother's obligation to take that woman as his wife, so that the first son that was born would be named after the dead brother, so that the family's name would continue in Israel.
In the book of Genesis, about the thirty-eighth chapter or so, we find that Judah had a son who took a gal as his wife, and he died without having any children. Tamar was the name of the wife. So the second son took her and he died without having any children. Judah was afraid to give the third son. So he said, "Well, he's too young to get married. Wait for him." Then long after the guy was old enough to get married, Judah hadn't really come through with the third son. So Tamar took things into her own hands. But it's a case where this law was being enacted, and Judah was in the wrong for withholding this son. It was just the law to keep the family name alive.
Now because Elimelech had died, and his two sons had died, the family name was about to die out. So she was actually asking Boaz to take the part of the goel, the kinsman redeemer, and to have a son by her that could be named after the family of Elimelech so that that name would not die as a family in Israel. Actually, what she was asking, "Cover me with this covering of the family, because you are a goel, you are the kinsman redeemer."

And he said to Ruth, Blessed be thou of the Lord, my daughter: for you have showed more kindness at the latter end than at the beginning, inasmuch as you followed not the young men, whether they were poor or rich (Ruth 3:10).

Now Boaz was probably an older man. He was very flattered that this younger girl, rather than following after these young guys would ask him to fulfill this kinsman relationship, this goel kinsman redeemer relationship. Again notice his, "Blessed be thou of the Lord," he shows all the way through good, godly characteristics.
And he said,

Now my daughter, fear not; for I will do unto you all that you require: for all the city of my people know that you are a virtuous woman (Ruth 3:11).

Ruth's reputation had gotten around. She was a virtuous girl. Her taking care of her mother-in-law, her whole attitude of really worshiping and serving God, word had gotten around concerning Ruth, "She's a virtuous girl." He said, "I will do all that the law requires and what you're requiring. Don't be afraid, I'm gonna do it.

But it is true that I am a near kinsman: ["I'm a close family relative."] however there is a kinsman that is closer than I am. Now you tarry tonight, and in the morning, [if he will not perform unto thee or,] if he will perform to you the part of a kinsman, fine; let him perform unto thee: but if he will not do the part of a kinsman to thee, then will I do the part of a kinsman to thee, as the Lord liveth: lie down until morning (Ruth 3:12-13).

Now not always would they fulfill this part. Sometimes they didn't like the gal. Their brother married sort of-all right, you. And he died and he didn't have any children, and you say, "Hey no way I don't want her."
So you take off your shoe and hand it to her like "Hey you're a dirty shoe as far as I'm concerned." You're giving up your right. "I don't want to marry you. I don't want to have anything to do with you." She then would spit in your face, and you would be called "The man from whom the shoe was loosed in Israel." You were considered sort of a dirty dog kind of a guy because you didn't fulfill the family obligations, no family loyalty. So that was the little ritual and that oftentimes happened. The fellow didn't want to carry through. "I don't want to marry her. I don't want the obligations of her, not interested." So he'd take off his shoe and hand it to her.
So he said, "Ruth, don't worry I will do it." But the hitch is there's another fellow who is actually closer of kin and he has the right first to be the kinsman. "If he is, fine, but if he doesn't then I will be the kinsman unto thee. I will raise up a child, and I will take you as my wife, and I will fulfill this obligation. So don't worry one way or the other it's gonna be taken care of."
So he said, "Lie down until morning."

And so she lay at his feet until morning: and she rose up before any one could know each other. [In other words it was still so dark you couldn't recognize anybody.] And he said, Don't let it be known that a woman was on the threshingfloor tonight. And so he said, Bring me the veil that you had on you, and she held it. And when she held it, he measured out six measures of barley, and laid it on her: and she went into the city. And when she came to her mother in law, [It was still dark, and so, Naomi said, "Who is it?"] and she said, Who art thou, my daughter? And so Ruth told her all that Boaz had said and done. And she said, These six measures of barley he gave to me; for he said, Don't go empty to your mother in law. Then Naomi said, [She's a wise old gal, she's been around. She said,] Sit still, my daughter, until you know how the matter will fall: for this man will not rest, until he's gotten everything taken care of (Ruth 3:14-18). "