Old Testament readings use the Septuagint , the Scripture the apostles quoted. Masoretic numbering shown for reference.Learn why
KJV

Judges 9:18

And ye are risen up against my father’s house this day, and have slain his sons, threescore and ten persons, upon one stone, and have made Abimelech, the son of his maidservant, king over the men of Shechem, because he is your brother;)

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