The Judaizers taught that people must follow the Law of Moses to become Christians.
The Judaizers taught that people must follow the Law of Moses to become Christians.

The Judaizers were a group of early Christians that included both Jewish and non-Jewish converts to the faith. They insisted that all converts must identify with the nation of Israel and observe the Law of Moses in order to truly have the favor of God. Most scholars believe that Paul's letter to the Galatians was written to refute the Judaizers' teaching.

Circumcision

The Judaizers taught that all male converts to Christianity must undergo circumcision, an operation in which the foreskin of the penis is cut off. Their basis for this belief came from the book of Exodus, in which Moses taught that foreigners who wanted to celebrate Passover -- the Jewish celebration of their deliverance from slavery in Egypt -- needed to become circumcised and follow the same law as other Israelites. This presented obvious problems for many potential male converts.

Law of Moses

In addition to circumcision, the Judaizers insisted that gentile converts obey the rest of the Law of Moses. This included dietary requirements which would have seemed strange to gentile converts, such as prohibitions against pork and shellfish. In his letter to the Galatians, Paul affirms that those who submit to the Judaizers' teachings would need to obey the entire law -- something he thought that even the Judaizers were incapable of.

Separatism

The Judaizers insisted on a separation between Jewish Christians and gentile Christians. Those who were of Jewish heritage continued to worship at Jewish temples, and otherwise continued to be involved in Jewish worship and practice. This was the norm for most early Christians of Jewish heritage, including Paul, and most scholars agree that it only became an issue when the Judaizers refused to break bread with gentile Christians, creating the potential for division.

Sacred Days

The Judaizers insisted that gentile converts to Christianity observe all of the Jewish holy days in keeping with the Law of Moses. This teaching is addressed in Romans 14:5 and Colossians 2:16, in which Paul teaches that there's nothing wrong with observing the holy days, but that those who choose to should not judge those who don't.

Council of Jerusalem

Disagreements between the Judaizers and Paul and his fellow missionaries over how much of the Law of Moses and Jewish tradition applied to gentile Christians eventually led to the Council of Jerusalem around A.D. 50. According to Acts 15, James -- one of the prominent leaders in the church in Jerusalem -- suggested that they should not seek to make conversion difficult for gentiles. James said that the only parts of the Law which should be insisted upon were those that had to do with idol worship, sexual immorality and the eating of strangled animals and blood. Scholars note that the last requirement was probably included to avoid a practice that would have been particularly offensive to Jewish Christians.