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

Deuteronomy 31:21

And this song shall stand up to witness against them; for they shall not forget it out of their mouth, or out of the mouth of their seed; for I know their wickedness, what they are doing here this day, before I have brought them into the good land, which I swore to their fathers.

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