3 This is what the Lord says to the people of Judah and to Jerusalem:
“Break up your unplowed ground
and do not sow among thorns.
4 Circumcise yourselves to the Lord,
circumcise your hearts,
you people of Judah and inhabitants of Jerusalem,
or my wrath will flare up and burn like fire
because of the evil you have done—
burn with no one to quench it.
This is a call to wholehearted repentance for the people of Jerusalem and Judah. The Lord uses two images to describe this repentance. The first is breaking up unplowed ground and removing the weeds so the soil is ready for planting. This is a metaphor for softening the people’s hearts to hear and heed God.
The second image is circumcision, but God makes it clear that he is not talking about merely fleshly circumcision. Rather, he calls the people to circumcise their hearts. Moses made this same appeal to the people of Israel, and commanded them to stop being “stiff-necked,” that is, to quit being stubborn and resistant to God and his Word. To have a circumcised heart means one’s heart is receptive and responsive to God and his Word. Both Moses and Jeremiah say that God himself will accomplish this circumcision by writing his law on people’s hearts when he makes a new covenant.
This is likely what Paul has in mind when he describes baptism into Christ as being “circumcised with a circumcision not performed by human hands”. He describes this spiritual circumcision as the removal of the “flesh,” our old fallen identity. In Christ, the new covenant has come, God’s Spirit has been poured out and we have been given a new heart, one that can and does obey God wholeheartedly.
