But he is a Jew, who is one inwardly; and circumcision is that of the heart, in the spirit, and not in the letter; whose praise is not of men, but of God.
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It is clear why Paul denies that the circumcision of the flesh has any merit with God. For Abraham was not justified because he was circumcised; rather, he was justified because he believed, and afterward he was circumcised. It is the circumcision of the heart which is praiseworthy before God. To circumcise the heart means to cut out error and recognize the Creator. And because the circumcision of the heart was to come in the future, first Moses said: “Circumcise the hardness of your heart,” and Jeremiah also: “Circumcise the foreskin of your heart.” He said this to Jews who were following idols. For there is a veil over the heart which the one who is converted to God circumcises, because faith removes the cloud of error and grants those who are perfect knowledge of God in the mystery of the Trinity, which was unknown in earlier times. The praise of this circumcision is from God but is hidden to men, for it is the merit of the heart which God looks for, not that of the flesh. But the p...
This means that the law should be understood according to the Spirit, and not according to what the letter says. This pertains especially to those who have interpreted circumcision more according to the flesh than according to the Spirit.
For he possesses in its sincerity the faith which is exercised in reference to the affairs of life, and praises the Gospel in practice and contemplation. And, in truth, he wins his praise "not from men, but from God"
By saying this Paul sets aside everything which is merely of the body. For the circumcision is external, and so are the sabbaths, the sacrifices and the purifications…. The Gentile who does right is more praiseworthy than the Jew who breaks the law. When this is agreed upon, the circumcision of the flesh must be set aside, and the need for a good life is everywhere demonstrated.