'Of the Circumcision' in the Bible

So He let Moses alone [to recover]. At that time Zipporah said, “You are a husband of blood”—because of the circumcision.

Before certain men came from James, he used to eat [his meals] with the Gentiles; but when the men [from Jerusalem] arrived, he began to withdraw and separate himself [from the Gentile believers], because he was afraid of those from the circumcision.

and from Jesus, who is called Justus. These are the only fellow workers for the kingdom of God who are from the circumcision (Jewish Christians), and they have proved to be an encouragement and a comfort to me.

For there are many rebellious men who are empty talkers [just windbags] and deceivers; especially those of the circumcision [those Jews who insist that Gentile believers must be circumcised and keep the Law in order to be saved].