Judaizers were Jewish Christians that insisted that Gentile converts to Christianity abide by certain Old Testament rites.

Judaizers were Jewish Christians who believed that a number of ceremonial practices of the Old Testament were still binding on the New Testament church.  Following Paul’s successful campaign in Galatia, they insisted that Gentile converts to Christianity abide by certain Old Testament rites, especially circumcision.  This is still prevalent in the church. It is so easy as believers to impose our expectations, traditions and attitudes on new Christians. In Paul’s teaching, this is akin to waiting for someone to walk out of the hospital so you can cough on them and infect them with a new disease.