30:6 the Lord . . . will circumcise your heart. See notes on vv. 1–10 and 10:16. The promised restoration and renewal will result from a sovereign work of God in the hearts of His elect. By circumcising (transforming) their hearts, He will replace their total inability and stubbornness (5:29; 10:16; 29:4) with the humility and repentance they need (cf. vv. 1, 2), purifying for Himself a people who will love and obey Him. See “Legalism” at Matt. 23:4.