Joshua at the Western Confucian linked to an essay by the Restrained Radical regarding the practice of circumcision and the sinfulness thereof a subject of which I, as a student of things Judaic, found to be somewhat wide of the mark with regards to the proper teaching of the Church:
His main source is a proclamation from Pope Eugene IV (1441) (Note the lack of "Pope St. Eugene". Not to impugn his authority, but perhaps his spiritual insight and theological depth).
and that whoever, even after the passion, placed hope in these matters of the law and submitted himself to them as necessary for salvation, as if faith in Christ could not save without them, sinned mortally. Yet it does not deny that after the passion of Christ up to the promulgation of the Gospel they could have been observed until they were believed to be in no way necessary for salvation; but after the promulgation of the Gospel it asserts that they cannot be observed without the loss of eternal salvation. All, therefore, who after that time observe circumcision and the Sabbath and the other requirements of the law, it declares alien to the Christian faith and not in the least fit to participate in eternal salvation, unless someday they recover from these errors. Therefore, it commands all who glory in the name of Christian, at whatever time, before or after baptism, to cease entirely from circumcision, since, whether or not one places hope in it, it cannot be observed at all without the loss of eternal salvation.
OK, a few things:
"placed hope in these matters of the law and submitted himself to them as necessary for salvation, as if faith in Christ could not save without them, sinned mortally"
This part is actually pretty good. No Christian, whether Jew or Greek is bound to the Mosaic law, and the following of Mosaic observances is, of itself, not availing to salvation. However, there are a great many things that fall into that category. Use of sacramentals, private devotions, extra and para-liturgical prayer, etc., anyone who engaged in any of these in replacement of Christ and the sacraments, or in the belief that these are of themselves insufficient or unavailing, has committed a grave fault indeed.
However context here is crucial, and there have been, and were at the time of this decree, breakaway movements that asserted that observance of the Mosaic law, including circumcision, as well as communion under both species, observance of Saturday Sabbath rather than Sunday, or were necessary for salvation.
All, therefore, who after that time observe circumcision and the Sabbath and the other requirements of the law, it declares alien to the Christian faith and not in the least fit to participate in eternal salvation, unless someday they recover from these errors
This language is clearly aimed at groups purporting to be within the Church, as it is nothing but a tautological statement with relation to Jews. I might also add that I know Jewish converts who "keep kosher" not out of obligation, but as a private devotion, out of love, rather than fear, and such pure acts are neither reprimanded nor reprobated by the Church today as they are not being performed out of a misguided theology.
Therefore, it commands all who glory in the name of Christian, at whatever time, before or after baptism, to cease entirely from circumcision, since, whether or not one places hope in it, it cannot be observed at all without the loss of eternal salvation.
OK, here it gets really clear that this decree is in response to schismatic group rather than Jews. I would quibble with the "glory in the name of Christian before or after baptism, as there is no such thing as an unbaptized Christian. I would also add that the Pope has no authority to command living non-Christians, devils or evil spirits of non-Christians yes. He also ignores the medical reasons that were known even at the time (See Herodotus). As for any devotional aspects, this is problematic as it runs up against the injunctions against mutilation, and is clearly superseded by Baptism anyway. But as the practice may in places both have a social aspect not present in Europe (either in the Middle Ages or Today: Witness Christopher Hitchens' disgusting perorations on circumcision) which may well be said for other practices insofar as they are not (within reason) intrinsically physically harmful such as tattooing, piercing, branding, or scarification, and, particularly in the case of infants, and pose little risk of functional injury or impairment (much less than tattooing in fact!), I do not think that the reprobation of Eugene IV applies in the context of where circumcision is performed today.
The main Reasons Being:
(1) The child is a practicing Jew
(2) Medical considerations
(3) General Social Norms
Remember God instituted circumcision among the Jews. God is incapable or instituting an intrinsically immoral institute. It all hangs on why the circumcision is taking place.