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

2 Chronicles 25:5

And Amasias assembled the house of Juda, and appointed them according to the houses of their families for captains of thousands and captains of hundreds in all Juda and Jerusalem: and he numbered them from twenty years old and upwards, and found them three hundred thousand able to go out to war, holding spear and shield.

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