2SA 17:25

25 And Absalom ordained Amasa for Joab upon his host; and Amasa was the son of a man that was called Ithra of Jezreel, the which entered to Abigail, the daughter of Nahash, (and) the sister of Zeruiah, that was the mother of Joab. (And Absalom ordained Amasa uponhis army, in Joab’s place; and Amasa was the son of a man called Ithra, an Ishmaelite, who entered in to Abigail, who was Nahash’s daughter, and Zeruiah’s sister, Joab’s mother.)