2 Samuel 17:25
And Absalom made Amasa captain of the host instead of Joab: which Amasa was a man's son, whose name was Ithra an Israelite, that went in to Abigail the daughter of Nahash, sister to Zeruiah Joab's mother.
Nave's Topical Index

1 Chronicles 2:17
And Abigail bore Amasa: and the father of Amasa was Jether the Ishmeelite.
Nave's Topical Index

Book 5 Footnotes
... that Joab, Abishai, and Asahel were all three David's nephews, the sons of his sister
Zeraiah, as 1 Chronicles 2:16; and that Amasa was also his nephew by his ...
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