2 Samuel 17:25

25Now Absalom had set aAmasa over the army instead of Joab. Amasa was the son of a man named Ithra the Ishmaelite,
Compare 1 Chronicles 2:17; Hebrew Israelite
who had married Abigal the daughter of cNahash, sister of Zeruiah, Joab’s mother.

1 Chronicles 2:16-17

16And their sisters were Zeruiah and Abigail. dThe sons of Zeruiah: Abishai, Joab, and Asahel, three. 17 eAbigail bore Amasa, and the father of Amasa was fJether the Ishmaelite.

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