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

Deuteronomy 30:20

to love the Lord thy God, to hearken to his voice, and cleave to him; for this [is] thy life, and the length of thy days, that thou shouldest dwell upon the land, which the Lord sware to thy fathers, Abraam, and Isaac, and Jacob, to give to them.

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