Deuteronomy 30:6 - Joseph Benson’s Commentary on the Old and New Testaments

And the Lord Or, For the Lord; will circumcise thy heart Will by his word and Spirit change and purge thy heart from all thy idolatry and wickedness, and incline thy heart to love him. God will first convert and sanctify thee, the fruit whereof shall be, that thou shalt return and obey God's commandments, (Deuteronomy 30:8,) and then shalt prosper in all things, Deuteronomy 30:9. This promise principally respects the times of the gospel, and still remains to be accomplished, at least in the full sense; for, though after the Babylonish captivity they never returned to idolatry, yet they degenerated into endless superstitions and corruptions of heart, resting merely in the outward ceremonies of religion, without any sincere love to God and substantial piety. Hence they rejected the Son of God, preaching conversion of heart, regeneration, spiritual worship, and a kingdom not of this world.