Old Testament readings use the Septuagint , the Scripture the apostles quoted. Masoretic numbering shown for reference.Learn why
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Jeremiah 41:9

Now the pit in which Ishmael cast all the dead bodies of the men whom he had killed, by the side of Gedaliah (this was that which Asa the king had made for fear of Baasha king of Israel), Ishmael the son of Nethaniah filled it with those who were killed.

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