Purpose
Judaizers were Jewish Christians who believed, among other things, that a number of the ceremonial practices of the OT were still binding on the NT church. Following Paul's successful campaign in Galatia, they insisted that Gentile converts to Christianity abide by certain OT rites, especially circumcision. They may have been motivated by a desire to avoid the persecution of Zealot Jews who objected to their fraternizing with Gentiles (see Gal 6:12). The Judaizers argued that Paul was not an authentic apostle and that out of a desire to make the message more appealing to Gentiles he had removed from the gospel certain legal requirements.

Paul responded by clearly establishing his apostolic authority and thereby substantiating the gospel he preached. By introducing additional requirements for justification (e.g., works of the law) his adversaries had perverted the gospel of grace and, unless prevented, would bring Paul's converts into the bondage of legalism. It is by grace through faith alone that people are justified, and it is by faith alone that they are to live out their new life in the freedom of the Spirit.

Teaching

Galatians stands as an eloquent and vigorous apologetic for the essential NT truth that people are justified by faith in Jesus Christ -- by nothing less and nothing more -- and that they are sanctified not by legalistic works but by the obedience that comes from faith in God's work for them, in them and through them by the grace and power of Christ and the Holy Spirit. It was the rediscovery of the basic message of Galatians (and Romans) that brought about the Protestant Reformation. Galatians is often referred to as "Luther's book," because Martin Luther relied so strongly on this letter in all his preaching, teaching and writing against the prevailing theology of his day. It is also referred to as the "Magna Carta of Christian Liberty." A key verse is Gal 2:16.