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

Deuteronomy 16:15

Seven days shalt thou keep a solemn feast unto the Lord thy God in the place which the Lord shall choose: because the Lord thy God shall bless thee in all thine increase, and in all the works of thine hands, therefore thou shalt surely rejoice.

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