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

1 Samuel 6:19

And he smote the men of Beth–shemesh, because they had looked into the ark of the Lord, even he smote of the people fifty thousand and threescore and ten men: and the people lamented, because the Lord had smitten many of the people with a great slaughter.

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