Naomi - “fair or pleasant”; and their two sons, Mahlon and Chilion, are supposed to be the same as Joash and Saraph (1Ch 4:22).
Ephrathites - The ancient name of Beth-lehem was Ephrath (Gen 35:19; Gen 48:7), which was continued after the occupation of the land by the Hebrews, even down to the time of the prophet Micah (Mic 5:2).
Beth-lehem-judah - so called to distinguish it from a town of the same name in Zebulun. The family, compelled to emigrate to Moab through pressure of a famine, settled for several years in that country. After the death of their father, the two sons married Moabite women. This was a violation of the Mosaic law (Deu 7:3; Deu 23:3; Ezr 9:2; Neh 13:23); and Jewish writers say that the early deaths of both the young men were divine judgments inflicted on them for those unlawful connections.