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

Judges 20:45

And the rest turned, and fled to the wilderness to the rock of Remmon; and the children of Israel picked off of them five thousand men; and the children of Israel went down after them as far as Gedan, and they smote of them two thousand men.

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