Schaff's Bible Dictionary
GALATIANS, EPISTLE TO, written by Paul with his own hand (ch. d. 65-58. Its design is to diffuse true notions among the Galatian Christians concerning justification, the relation of the Mosaic economy to the Christian, and the authority of Paul as an apostle. The Galatians had received Paul with much enthusiasm when he first preached the gospel to them, Gal 4:15. After his departure teachers had disseminated the false idea that the obligation was incumbent upon the followers of Christ to practise the ceremonies and rites of the Mosaic code.
With much vehemence and fervor Paul combats their Judaizing teachings, and enforces the doctrine that by faith alone are we justified. Faith constitutes one the child of Abraham, Lev 3:9, and circumcision is not only not essential to salvation, but is in itself of no avail. 1 Kgs 6:6. Chs. 1 and 2 are occupied mainly with a vindication of Paul's apostolic commission as of equal authority with that of the other apostles, and with an account of a debate concerning meats at the council of Jerusalem. Chs. 5 and 6 contain practical exhortations.
The main argument, that we become partakers of salvation by faith, Gal 3:26, is the same in the Epistle to the Galatians as in that to the Romans. The two Epistles were best understood in the time of the Reformation, and form the magna charta of evangelical Protestantism.