1 Chronicles 7:13 lists the sons of Naphtali as Jahziel, Guni, Jezer, and Shallum, and notes that they were descendants of Bilhah. This verse is part of a genealogy, recording the family line of the tribe of Naphtali among the tribes of Israel.
The book of 1 Chronicles was written to preserve the history and lineage of Israel’s tribes, especially after the exile. Here, the chronicler is listing the descendants of Naphtali, one of Jacob’s twelve sons, for the purpose of documenting the nation’s ancestry. The mention of Bilhah, who was Rachel’s maidservant and the mother of Naphtali, reminds the reader of the complex family relationships in Israel’s early history.