Circumcision, to be sure, has value if you observe the law, but if you
break it you might as well be uncircumcised!  Again, if an
uncircumcised person keeps the precepts of the law, will he not be
considered circumcised?  If a man who is uncircumcised keeps the law,
he will pass judgment on you who, with your written law and circumcision,
break it.  Appearance does not make a Jew.  True circumcision is not a
sign in the flesh.  He is a real Jew who is one inwardly, and true
circumcision is of the heart; its source is the spirit, not the letter.
Such a one receives his praise, not from men, but from God.

The New American Bible, Catholic Bible Publishers, Wichita, Kansas, Copyright 1970, 1978-1979 Edition.
Stephen J. Hartdegen, O.F.M., S.S.L.
Christian P. Ceroke, O.Carm., S.T.D.
Patrick Cardinal O’Boyle, D.D., Archbishop of Washington