‘ And he said to the near kinsman, “Naomi, who is come again out of the country of Moab, is selling the parcel of land, which was our brother Elimelech's.”
Then Boaz explained his purpose. He explained to the near kinsman that Naomi, who had recently come out of the country of Moab, was selling the family land which had belonged to her deceased husband, Elimelech. But as we have seen above, it was not as simple as that. For the land belonged to YHWH, and it had been allotted by Him to a family in Israel who was represented by the head of the family (who had in this case been Elimelech). What was therefore seen as of crucial importance was that ‘the name' of that family, in this case the family of Elimelech, should be maintained in Israel, and that would be done by the redeemer who bought the land begetting children through the surviving females in the family, where all the menfolk had died. This was the responsibility of the goel (redeemer).
As can be seen, the survival of the ‘name' of the family was seen as of vital importance. A man lived on in his sons, and no family was to be allowed to die out in Israel. It was the equivalent in the Old Testament of ‘eternal life'. Every means therefore had to be used in order to ensue the survival of the family name.
The question may arise as to whether Naomi was able to sell the land. Legally speaking it was not hers, and had it been a question of simply selling the land the answer would probably have been ‘no'. But that is not the case here. The land was being sold conditionally on the purchaser producing a male heir to finally inherit the land. In fact the right of women to inherit was declared in Numbers 36. There the daughters of a deceased man were able to inherit his land where there were no sons, the only condition being that they would then marry within their tribe so that possession of the land would not go outside the tribe. So it would appear here that legally the land could be seen as Ruth's, as wife of Elimelech's heir, but on that basis she would only enjoy the right as long as she married within her dead husband's tribe. While the position was not quite the same, Numbers 36 did suggest that where all male direct heirs within a family were dead, women could have an inheritance in the land of that family as long as when they married it remained within ‘the family'. This was probably the basis on which the sale here was able to proceed, with the sale being restricted to someone who could produce sons on behalf of the dead. In consequence the land would finally pass on to male heirs of Elimelech and Mahlon. From the point of view of the story what, of course, matters is not what exactly the Law said, but how it was being interpreted at this time in the light of custom.