Old Testament readings use the Septuagint , the Scripture the apostles quoted. Masoretic numbering shown for reference.Learn why
LXX2012

Deuteronomy 7:12

And it shall come to pass when you⌃ shall have heard these ordinances, and shall have kept and done them, that the Lord your God shall keep for you the covenant and the mercy, which he swore to your fathers.

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