SCHOLARS DISAGREE SOMEWHAT over the social significance of each action taken in Ruth 3-4, but the general line is clear enough.
Almost certainly the levirate laws, which allowed or mandated men to marry widowed in-laws under certain circumstances to keep the family name alive, were not followed very consistently. Following Naomi's instruction, Ruth takes a little initiative: she lies down at Boaz's feet in a "men only" sleeping area. When he wakes up, she says, "Spread the corner of your garment over me, since you are a kinsman-redeemer" (Ruth 3:9). This was an invitation, but not a cheap one. It signaled her willingness to become his wife, if Boaz will discharge his duties as a kinsman-redeemer. Boaz takes this as a compliment: apparently there is enough difference between their ages (Ruth 3:10, plus his habit of referring to Ruth as "my daughter") that he is touched by her willingness to marry him instead of one of the young men.
The story plays out with romantic integrity. Hollywood would hate it: there is no blistering sex, certainly not of the premarital variety. But there is a seductive charm to the account, allied with a wholesome respect for tradition and procedure, and a knowing grasp of human nature. Hence, Naomi confidently predicts that Boaz "will not rest until the matter is settled today" (Ruth 3:18).
She is right, of course. The town gate is the place for public agreements, and there Boaz marshals ten elders as witnesses and gently demands that the one person who is a closer relative to Naomi (and therefore with the right of "first refusal") discharge the obligations of kinsman-redeemer or legally abandon the claim (Ruth 4:1-4).
Apparently at this point the marriage rights are tied to ownership of the land of the deceased husband. This particular kinsman-redeemer would love to obtain the land, but does not want to marry Ruth. Her firstborn son in such a union would maintain the property and family heritage of the deceased husband; later sons would inherit from the natural father. But the situation is messy. Suppose Ruth bore only one son?
So Boaz marries Ruth, and in due course she gives birth to a son, whom they call Obed. Naomi is provided not only with a grandson, but with a family eager and able to look after her.
At one level, this is a simple story of God's faithfulness in the little things of life, at a time of social malaise, religious declension, political confusion, and frequent anarchy. God still has his people — working hard, acting honorably, marrying, bearing children, looking after the elderly. They could not know that Obed's was the line that would sire King David — and, according to the flesh, King Jesus