There is some question of how the Biblical texts on redemption of property and levirate marriage fits the situation with Ruth – it is Naomi’s property to be restored and her family line to be perpetuated, but that goes through Ruth.
Here is a background quote that gives perspective.
“…one must recall the nature of biblical legal materials. Against popular impression, they do not offer a comprehensive instruction which covers every imaginable case. Rather, they constitute instructions about sample or crucial topics from which inferences about all other cases are to be drawn. Their goal s is more to inculcate Israel’s fundamental value system in its people than to provide handy legal references for judicial bodies. Thus, attempts to align the customs in Ruth precisely with the details of three frequently cited texts (Gen 38; Lev 25:25-34; Dt. 25:5-10) are unnecessary and ill-advised. On the contrary the value of such texts exceeds their simple, procedural details; rather, they are mirrors of Israel’s treasured values. With reference to Ruth, they reflect how strongly Israel valued the survival of families through descendants and family ownership of ancestral property.”
Robert L Hubbard, Jr, The Book of Ruth (NICOT), Eerdmans, 1988
I was recently part of a discussion on divorce and remarriage. A very strict legal reading of the NT texts might suggest prohibiting any remarriage and limiting divorce to only infidelity and abandonment. but are the NT “laws” to be read in that way, or are they case-law and expressions of values by which we should decide in particular cases what is to be done. In ministry one encounters many situations what require wisdom beyond a close reading of the rules.
A theme in Ruth is “hesed” a Hebrew word that means faith, often in the sense of faithfulness. God’s faithfulness to his people whom he has chosen. Boaz’s and Ruth’s faithfulness expressed in their actions and commitments.