circumcise your hearts

What does it mean to "circumsise your heart"?

The LORD your God will circumcise your hearts and the hearts of your descendants, so that you may love him with all your heart and with all your soul, and live. Deut 30.6

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.

 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.

And the LORD said to me, "I have seen this people, and they are a stiff-necked people indeed!

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.

On "circumcision" see Genesis 17:10. This verse points to the spiritual import of circumcision. Man is by nature "very far gone from original righteousness," and in a state of enmity to God; by circumcision, as the sacrament of admission to the privileges of the chosen people, this opposition must be taken away ere man could enter into covenant with God. It was through the flesh that man first sinned; as it is also in the flesh, its functions, lusts, etc., that man's rebellion against God chiefly manifests itself still. It was fitting therefore that the symbol which should denote the removal of this estrangement from God should be worked in the body. Moses then fitly follows up the command "to circumcise the heart," with the warning "to be no more stiff-necked." His meaning is that they should lay aside that obduracy and perverseness toward God for which he had been reproving them, which had led them into so many transgressions of the covenant and revolts from God, and which was especially the very contrary of that love and fear of God required by the first two of the Ten Commandments. The language associated with circumcision in the Bible distinguishes the use made of this rite in the Jewish religion from that found among certain pagan nations. Circumcision was practiced by some of them as a religious rite, designed (e. g.) to appease the deity of death who was supposed to delight in human suffering; but not by any, the Egyptians probably excepted, at all in the Jewish sense and meaning. The grounds on which circumcision was imposed as essential by the Law are the same as those on which Baptism is required in the Gospel. The latter in the New Testament is strictly analogous to the former under the Old; compare Colossians 2:11-12.