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

Deuteronomy 30:20

That thou mayest love the Lord thy God, and that thou mayest obey his voice, and that thou mayest cleave unto him: for he is thy life, and the length of thy days: that thou mayest dwell in the land which the Lord sware unto thy fathers, to Abraham, to Isaac, and to Jacob, to give them.

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