"... Ruth’s story concludes with the birth of her son, Obed. This sign of fertility and continuity resolves the problem of famine and death that set Ruth and Naomi’s narrative in motion. The genealogy, then, situates Obed’s climactic birth in the larger biblical narrative, connecting him both to those who came before (back to Perez) and those who would come after (King David). While Ruth does not explicitly appear in the genealogy, the placement of the genealogy at the end of her story creates a close association between Ruth and the genealogy. This is an “intratextual” relationship between the narrative and genealogical portions of the book. The genealogy is Ruth’s genealogy, whether she is named in it or not, because of its placement in her book and its role as an epilogue to her narrative. By including Ruth in his genealogy, the author of Matthew was simply making explicit what was already implicit in the book of Ruth—Ruth’s presence in the genealogy. In addition, there is a close connection between Ruth and Tamar who, as we have already seen, is already a part of the genealogical tradition. Elle van Wolde has traced the many connections between the stories of Ruth and Tamar, including key words, plot, the role of the narrator, and the roles of the characters.63 Van Wolde does not use Genettes’ terminology, but she describes what Genette calls a heterodiegetic transformation.64 That is, basic structures of the story remain the same, while the setting and certain features of the characters change. Also, van Wolde’s identification of several humorous sexual double entendres in Ruth suggest that the tone of Ruth’s hypertextuality in relationship to Genesis 38 is not wholly serious, and contains an element of parody ..."

Rosenberg, Gil "Hypertextuality" in Oropeza, Brisio J., and Steve Moyise, (eds.) Exploring Intertextuality: Diverse Strategies for New Testament Interpretation of Texts (pp. 40-55) Cascade Books, 2016