they will not do it until they return to their home in Jerusalem again — that is to say, when the devil ascends into heaven. For when they assert that God enjoined circumcision for the purpose of sanctifying them, saving them, making them God's people, they are lying atrociously, as you have heard. For Moses and all the prophets testify that circumcision did not help even those for whom it was commanded, since they were of uncircumcised hearts. How, then, should it help us for whom it was not commanded?
But to speak for us Christians — we know very well why it was given or what purpose it served. However, no Jew knows this, and even when we tell him it is just like addressing a stump or a stone. They will not desist from their boasting and their pride, that is, from their lies. They insist that they are in the right; God must be the liar and he must be in error. Therefore, let them go their way and lie as their fathers have done from the beginning. But St. Paul teaches us in Romans 3 that when circumcision is performed as a kind of work it cannot make holy or save, nor was it meant to do so. Nor does it damn the uncircumcised Gentiles, as the Jews mendaciously and blasphemously say. Rather, he says, "circumcision is of great value in this way — that they were entrusted with the word of God" [cf. Rom. 3:1 ff.]. That is the point, there it is said, there it is found! Circumcision was given and instituted to enfold and to preserve God's word and his promise. This means that circumcision should not be useful or sufficient as a work in itself, but those who possess circumcision should be bound by this sign, covenant, or sacrament to obey and to believe God in his words and to transmit all this to their descendants.
But where such a final cause or reason for circumcision no longer obtained, circumcision as a mere work no longer was to enjoy validity or value, all the more so if the Jews should patch or attach another final cause or explanation to it. This is also borne out by the words in Genesis 17: "I will be your God, and in token of this you shall bear my sign upon your flesh" [cf. Gen. 17:8,