Ithra: Father of Amasa
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2 Samuel 17:25
Absalom had appointed Amasa over the army in place of Joab. Amasa was the son of a man named Ithra, the Ishmaelite who had married Abigail, the daughter of Nahash and sister of Zeruiah the mother of Joab.
1 Chronicles 2:17
Abigail was the mother of Amasa, whose father was Jether the Ishmaelite.