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

Deuteronomy 16:15

Seven days shalt thou keep a feast to the Lord thy God in the place which the Lord thy God shall choose for himself; and if the Lord thy God shall bless thee in all thy fruits, and in every work of thy hands, then thou shalt rejoice.

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