Charles Ellicott Commentary Jeremiah 9:25

"Behold, the days come, saith Jehovah, that I will punish all them that are circumcised in [their] uncircumcision:" — Jeremiah 9:25 (ASV)

I will punish all them which are circumcised with the uncircumcised. —The passage is difficult, but the English verse is misleading. Better, I will punish all those that are circumcised in uncircumcision—all, that is, who have the outward sign, but not the inward purity of which it was the symbol.

In the day of God’s judgments (this being the connecting link with the preceding verse), there would be no difference between the Jew and other races who, like him, practised circumcision on the one hand, and the outlying Gentile world on the other. Here, again, Jeremiah anticipated St. Paul: To the Jew first, and also to the Gentile; for there is no respect of persons with God (Romans 2:9). The true circumcision is that which is in the spirit, not in the letter (Romans 2:29).