Later he more explicitly denounced the practice, rejecting and condemning those who promoted circumcision to Gentile Christians. He accused those Judaizers who advocated circumcision of turning from the Spirit to the flesh. In the Epistle to the Galatians, Paul warned Gentile Christians that the advocates of circumcision were "false brothers" (), and wrote: "Are you so foolish, that, whereas you began in the Spirit, you would now be made perfect by the flesh?" (); he also wrote: "Listen! I, Paul, am telling you that if you let yourselves be circumcised, Christ will be of no benefit to you" (). He accused circumcision advocates of wanting to make a good showing in the flesh (), and of glorying or boasting of the flesh (). Paul in his letters fiercely criticized the Judaizers that demanded circumcision for Gentile converts, and opposed them; he stressed instead that faith in Christ constituted a New Covenant with God, a covenant which essentially provides the justification and salvation for Gentiles from the harsh edicts of the Mosaic Law, a New Covenant that didn't require circumcision (see also Justification by faith, Pauline passages supporting antinomianism, Abrogation of Old Covenant laws).