Charles Ellicott Commentary 1 Chronicles 4:2

"And Reaiah the son of Shobal begat Jahath; and Jahath begat Ahumai and Lahad. These are the families of the Zorathites." — 1 Chronicles 4:2 (ASV)

Reaiah (or Jehoraah) the son of Shobal ... —See 1 Chronicles 2:52, which also calls Shobal father of Kirjath-jearim. 1 Chronicles 2:53 adds that the Zorathites (Authorised Version, Zareathites) came from the clans of Kirjath-jearim. The present verse supplements the data of 1 Chronicles 2:0, by putting the clans of Zorah in immediate genealogical connection with Shobal. Their names—Ahumai and Lahad—occur nowhere else.